Patent Publication Number: US-2022229255-A1

Title: Bladed chassis systems

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 17/104,758, filed Nov. 25, 2020, which is a continuation of U.S. application Ser. No. 16/518,464, filed Jul. 22, 2019, now U.S. Pat. No. 10,852,500, which is a continuation of U.S. application Ser. No. 15/650,539, filed Jul. 14, 2017, now U.S. Pat. No. 10,359,593, which is a continuation of U.S. application Ser. No. 14/747,854, filed Jun. 23, 2015, now U.S. Pat. No. 9,709,765, which application claims the benefit of U.S. Provisional Application No. 62/015,886, filed Jun. 23, 2014, titled “Bladed Chassis Systems;” U.S. Provisional Application No. 62/018,193, filed Jun. 27, 2014, titled “Bladed Chassis Systems;” U.S. Provisional Application No. 62/082,429, filed Nov. 20, 2014, titled “Bladed Chassis Systems,” and U.S. Provisional Application No. 62/159,084, filed May 8, 2015, titled “Bladed Chassis Systems,” which applications are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     In bladed chassis systems, optical adapters are mounted to one or more blades that are disposable within a chassis. The blades can slide forwardly of the chassis to enhance access to the optical adapters. Cable clamps, anchors, or other fasteners can be fixed to the rear of the chassis to secure incoming cables in fixed positions relative to the chassis. 
     Improvements are desired. 
     SUMMARY 
     The present disclosure relates generally to a bladed chassis system at which blades can be inserted and removed from the front and can be inserted and removed from the rear at the discretion of the user. In certain examples, a rear portion of the chassis opens to enable insertion and/or removal of the blades at the rear. In certain examples, a front portion of the chassis opens to enable insertion and/or removal of the blades at the front. 
     In accordance with some aspects of the disclosure, a chassis system includes a housing, a cable bracket, and a bracket cover. The housing includes first and second sidewalls extending between a bottom wall and a top wall to define an interior. The first and second sides also extend between an open front of the housing and an open rear of the housing. The cable bracket is coupled to the housing at the open rear. The cable bracket is configured to pivot relative to the housing between a first position and a second position. The cable bracket extends at least partially across the open rear when in the first position. The cable bracket does not extend across the open rear when in the second position. The bracket cover is coupled to the housing at the open rear. The bracket cover is configured to pivot relative to the housing between a first position and a second position. The bracket cover extends at least partially across the open rear when in the first position. The bracket cover does not extend across the open rear when in the second position. The bracket cover is configured to fasten to the cable bracket to hold the bracket cover and bracket in the first positions. 
     In certain examples, a blade is configured to mount within the interior of the housing, the blade including at least one optical adapter. In an example, the blade includes a plurality of optical adapters. In an example, the blade is configured to slide relative to the housing. 
     In certain examples, the blade includes a fiber management tray including a fiber spool. In examples, the blade includes two fiber management trays. In an example, the fiber management tray is configured to hold at least one fanout device. In an example, the fiber management tray is configured to hold a plurality of fanout devices. 
     In an example, the blade is removable from the interior of the housing through the open front. In an example, the blade is removable from the interior of the housing through the open rear when the cable bracket and the bracket cover are in the second positions. 
     In certain examples, a front panel is configured to removably couple to the chassis. The front panel extends across the open front of the chassis. In examples, arms extending forwardly of the housing, each arm defining a pivot hinge. The front panel includes slots sized to receive the pivot hinges of the arms to pivotally couple the front panel to the chassis. 
     In an example, the arms are mounted towards the top of the housing, wherein the blade is removable from the housing through the open front when the front panel is pivoted open. In an example, the arms are mounted towards the bottom of the housing. The blade is removable from the housing through the open front when the front panel is pivoted open. In an example, two of the arms are mounted towards the top of the housing and two of the arms are mounted towards the bottom of the housing. 
     In certain examples, the cable bracket is configured to receive a clamping assembly for holding one end of a cable to the cable bracket. The cable bracket carries the end of the cable as the cable bracket pivots between the first and second positions. 
     In accordance with other aspects of the disclosure, a blade arrangement for use in a chassis system includes a blade including a base extending between sidewalls that define outwardly facing slides; optical adapters disposed on the base; a fiber management tray disposed on the base; and forwardly extending arms having forward ends defining cable retainers. The optical adapters have forwardly facing ports and rearwardly facing ports. The fiber management tray includes a spool and a fanout holder that is configured to hold a fanout device. The fiber management tray defines a fastener opening that defines a rotational axis. The fiber management tray is configured to rotationally couple to the base in any desired rotational orientation about the rotational axis, thereby enabling any fanout device held by the fanout holder to be disposed in any desired rotational orientation about the rotational axis. 
     In examples, the fanout holder of the fiber management tray is configured to hold a second fanout device. In examples, at least some of the forwardly extending arms define mounts for the plurality of optical adapters. In an example, at least one of the forwardly extending arms is integral with the base. 
     In accordance with other aspects of the disclosure, a method of replacing a blade within a chassis system includes decoupling a bracket cover from a cable bracket at a rear of a chassis; pivoting the bracket cover and the cable bracket away from the chassis to reveal an open rear of the chassis; and sliding the blade out of the chassis through the open rear. The cable bracket carries a cable routed into the chassis through the rear of the chassis. 
     In certain examples, the method of replacing also includes sliding a replacement blade into the chassis through the open rear; pivoting the cable bracket to extend partially across the open rear; pivoting the bracket cover to contact the cable bracket, thereby closing the open rear; and coupling the bracket cover to the cable bracket. 
     In accordance with other aspects of the disclosure, a kit for installing a bladed chassis system includes a chassis housing defining an interior; a cable bracket that is mountable to an open rear of the chassis housing; and a bracket cover that is mountable to the chassis housing at the open rear. The cable bracket is pivotally coupled to the chassis housing at a selected one of the first side and the second side of the chassis housing. The cable bracket extends across a first portion of the open rear of the chassis housing when pivoted to a closed position. The cable bracket reveals the first portion of the open rear when pivoted to an open position. The bracket cover is pivotally coupled to the chassis housing at the other of the first side and the second side of the chassis housing. The bracket cover extends across a second portion of the open rear of the chassis housing when pivoted to a closed position. The bracket cover reveals the second portion of the open rear when pivoted to an open position. 
     In accordance with other aspects of the disclosure, a method of installing a bladed chassis system at a frame includes providing a bladed chassis system including a chassis, a cable bracket, and a plurality of blades. The cable bracket is pivotally coupled to a rear of the chassis to define an exposed cable port facing in a first direction and a covered cable port facing in a second direction that is different from the first direction. The method also includes determining whether the first side or the second side of the frame is a cabled side by determining whether a cable is disposed at the first side or the second side of the frame; orienting the chassis at the frame in a first orientation so that the exposed cable port faces towards the cabled side of the frame; mounting the cable to the cable bracket and closing the rear of the chassis with the cable bracket; and installing the blades in the chassis while the chassis is oriented in the first orientation. 
     In certain examples, the method also includes mounting a front panel to the chassis while the chassis is oriented in the first orientation. 
     In certain examples, the method also includes removing the blades from the chassis; moving the cable bracket to an open position and detaching the cable from the cable bracket; flipping the chassis upside-down into a second orientation and mounting the chassis in the second orientation; mounting the cable to the cable bracket and closing the rear of the chassis with the cable bracket; installing the blades in the chassis while the chassis is oriented in the second orientation; and mounting the front panel to the chassis while the chassis is oriented in the second orientation. 
     In accordance with other aspects of the disclosure, a chassis system includes a housing and blades configured to slide relative to the housing and to be retained within the housing. The housing includes first and second sidewalls extending between a bottom wall and a top wall to define an interior. The first and second sides also extend between an open front of the housing and an open rear of the housing. Each of the first and second sides includes a guide member. Each blade includes a latching arrangement configured to cooperate with the guide member to lock the blade into at least one discrete position and to allow the blade to selectively move relative to the housing between the discrete positions. 
     In certain implementations, the latching arrangement of each blade is configured to lock the blade into an operation position and into a connector access position, which is located forwardly of the operation position. In certain examples, the latching arrangement of each blade is configured to lock the blade into an adapter access position, which is located forwardly of the connector access position. In certain examples, each blade is further movable relative to the housing to a discrete position located rearwardly of the operation position. 
     In certain implementations, the blade is removable from the housing through the open front. In certain implementations, the blade is removable from the housing through the open rear. 
     In certain implementations, each guide member has an inner surface through which one or more channels are defined. The channels are elongated between the front and rear of the inner surface. Each channel is sized to receive the slide of one blade. A forward end of each channel is open to the front of the housing. Each channel defines a notch at a stop location along the channel. Each channel also defines a trough recessed rearwardly from the forward end of each channel. 
     In certain implementations, each latching arrangement includes a slide sized and shaped to ride along one of the channels of the guide member, two forward stop members disposed at opposite sides of the slide, and a rearward stop member that extends outwardly beyond the slide. The two forward stop members do not extend laterally outwardly beyond the slide. Each latching arrangement also includes a forward deflectable handle and a rearward deflectable handle. Deflection of the forward handle causes the forward stop members to move towards the blade and deflection of the rearward handle causes the rearward stop member to move towards the blade. 
     In certain examples, a spring is coupled to the blade to strengthen the forward handle. 
     In certain examples, a latch member also is coupled to the blade. The latch member has forward and rearward ends that pivot relative to the blade about the pivot location. The forward end of the latch body defines a handle. The rearward end of the latch body includes a stop member so that the stop member deflects laterally inwardly when the handle is deflected laterally outwardly. 
     In certain implementations, the guide member includes a rail configured to glide within a channel defined by the latching arrangement. In certain examples, the latching arrangement includes a body that supports a first handle, a second handle, and one or more stop members, each handle can be moved forwardly and rearwardly relative to the body along a travel distance. 
     A variety of additional inventive aspects will be set forth in the description that follows. The inventive aspects can relate to individual features and to combinations of features. It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the description, illustrate several aspects of the present disclosure. A brief description of the drawings is as follows: 
         FIG. 1  is a front perspective view of an example bladed chassis system including blades mounted within a chassis and a multi-fiber cable routed to a rear of the chassis; 
         FIG. 2  is a rear perspective view of the bladed chassis system of  FIG. 1 ; 
         FIG. 3  is a rear perspective view of the bladed chassis system of  FIG. 1  with a cable bracket and a bracket cover moved to open positions; 
         FIG. 4  is a perspective view of the bladed chassis system of  FIG. 3  from an opposite side of the system with the cable removed; 
         FIG. 5  is a perspective view of an example cable bracket suitable for use in bladed chassis systems; 
         FIG. 6  is a perspective view of an example clamping assembly suitable for use in bladed chassis systems; 
         FIG. 7  is a perspective view of an example bladed chassis system with the cable bracket and the bracket cover mounted to opposite sides compared to the bladed chassis system of  FIG. 3 ; 
         FIG. 8  is a perspective view of another example bladed chassis system; 
         FIG. 9  is a perspective view of an example blade suitable for use in any of the bladed chassis systems disclosed herein; 
         FIG. 10  is an enlarged view of a portion of  FIG. 9  with an adapter mounting arrangement exploded from a base of the blade; 
         FIG. 11  is a perspective view of another blade suitable for use in any of the bladed chassis systems disclosed herein; 
         FIG. 12  is an example fiber management tray suitable for use with any of the blades disclosed herein; 
         FIG. 13  is another example fiber management tray suitable for use with any of the blades disclosed herein; 
         FIG. 14  is a front perspective view of an example front panel mounted in a closed position to an example chassis; 
         FIG. 15  shows the front panel moved to a first open position relative to the chassis; 
         FIG. 16  is an enlarged view of  FIG. 15 ; 
         FIG. 17  shows the front panel moved to a second open position relative to the chassis; 
         FIG. 18  is an enlarged view of  FIG. 17 ; 
         FIG. 19  shows another example front panel mounted to the example chassis; 
         FIG. 20  is a perspective view of the bladed chassis system of  FIG. 1  with a first end wall and some of the blades removed to expose the guide channels; 
         FIG. 21  is an enlarged view of a portion of  FIG. 20 ; 
         FIG. 22  is a front perspective view of another example bladed chassis system including blades mounted within a chassis; 
         FIG. 23  shows a front panel opened to reveal an interior of the chassis of  FIG. 22 , a blade exploded from a front of the chassis, and a multi-fiber cable routed to a rear of the chassis; 
         FIG. 24  is a rear perspective view of the chassis of  FIG. 22  having multiple cable brackets and bracket covers and with multiple cables routed to the rear of the chassis; 
         FIG. 25  shows the bladed chassis system of  FIG. 24  without the mutli-fiber cables; 
         FIG. 26  shows the bladed chassis system of  FIG. 25  with one of the cable brackets and the corresponding bracket cover moved to the open position; 
         FIG. 27  shows the bladed chassis system of  FIG. 24  with only a single cable bracket and bracket cover and with a single cable routed to the rear of the chassis; 
         FIG. 28  shows the bladed chassis system of  FIG. 27  with the bracket cover moved to the open position; 
         FIG. 29  is a rear perspective view of an example blade configured to be utilized in any of the bladed chassis systems disclosed herein; 
         FIG. 30  is a front perspective view of another example blade configured to be utilized in any of the bladed chassis systems disclosed herein; 
         FIG. 31  is a front perspective view of an example cassette carrying adapters that can be mounted to the blade of  FIG. 30 ; 
         FIG. 32  is an exploded view of the cassette of  FIG. 31 ; 
         FIG. 33  is a front perspective view of an example hinge arrangement coupling an example chassis and an example front panel; 
         FIG. 34  is a side elevational view of the example hinge arrangement of  FIG. 33 ; 
         FIG. 35  is a perspective view of an example chassis holding an example blade; 
         FIG. 36  is a front perspective view of an example guide member of an example latching assembly; 
         FIG. 37  is a rear perspective view of the guide member of  FIG. 36 ; 
         FIG. 38  is a top plan view of an example latching arrangement suitable for use with the guide member of  FIG. 36 ; 
         FIG. 39  is an enlarged view of a portion of  FIG. 38  with the latch member disposed in an undeflected position; 
         FIG. 40  is a bottom view of the blade and latching arrangement of  FIG. 39  with hidden portions of the latch member shown in dashed lines; 
         FIG. 41  is an enlarged view of a portion of  FIG. 38  with the latch member disposed in a deflected position; 
         FIG. 42  is a bottom view of the blade and latching arrangement of  FIG. 41  with hidden portions of the latch member shown in dashed lines; 
         FIG. 43  is a perspective view of an example latching assembly suitable for use in guiding a blade along a chassis; 
         FIG. 44  is a perspective view of an example guide member along which a respective latching arrangement can slide; 
         FIG. 45  is an exploded view of an example latching arrangement suitable for use with the guide member of  FIG. 44 ; 
         FIG. 46  is a top plan view of portions of the latching arrangement of  FIG. 45 ; and 
         FIG. 47  is an axial cross-sectional view of the latching assembly of  FIG. 43  showing the positions of the stop members relative to the guide member when the blade is disposed in an operation position. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to exemplary aspects of the present disclosure that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
     The present disclosure relates generally to a bladed chassis system that facilitates installation of the bladed chassis system and replacement of the blades at the chassis. For example, in certain examples, a front panel of the blade can be opened either upwardly or downwardly at the discretion of the user. In certain examples, blades can be inserted and removed from the front and/or the rear of the bladed chassis system at the discretion of the user. In certain examples, cables can be routed to the rear of the chassis system from either of two sides at the discretion of the user. In certain examples, the blades carried by the chassis have fiber management trays that can be rotationally oriented in any desired rotational position at the discretion of the user. 
       FIGS. 1-3  illustrate one example bladed chassis system  100  including a chassis  110  and a blade  150 ,  160 . The chassis system  100  has a front  101 , a rear  102 , a top  103 , a bottom  104 , a first side  105 , and a second side  106 . The chassis  110  includes a housing  111  having two sidewalls  113  extending between a first end wall  112  ( FIG. 3 ) and a second end wall  114  ( FIG. 1 ). The first end wall  112 , sidewalls  113 , and second end wall  114  define an interior  115  ( FIG. 3 ) having an open front  116  and an open rear  117  ( FIG. 3 ). Interior surfaces of the sidewalls  113  define guide channels  118  at which the blades  150 ,  160  can be received (see  FIG. 3 ). Mounting brackets  119  are disposed at exterior surfaces of the sidewalls  113 . 
     The chassis system  100  is configured to receive one or more multi-fiber cables  190  at the rear  102  of the chassis system  100 . In certain examples, the chassis system  100  defines one or more side ports  108 ,  109  at the rear  102  of the chassis system  100 . As will be described in more detail herein, one or more multi-fiber cables  190  can be received and anchored at one of the ports  108 ,  109  at the discretion of the user. In certain implementations, the other of the ports  108 ,  109  can be covered to protect the optical fibers within the interior  115  of the chassis  110 . 
     A cable bracket  120  and a bracket cover  130  are mounted to the chassis housing  111  at the open rear  117 . Each of the cable bracket  120  and the bracket cover  130  are movable between an open position and a closed position. The cable bracket  120  and the bracket cover  130  cooperate to close the open rear  117  when both are disposed in the closed positions (see  FIG. 2 ). The cable bracket  120  and the bracket cover  130  also cooperate to define one of the side ports  108 ,  109  and to cover the other of the side ports  108 ,  109  when disposed in the closed positions. Moving both the cable bracket  120  and bracket cover  130  to the open positions reveals the open rear sufficient to enable a blade  150 ,  160  to be inserted and/or removed at the open rear  117  of the chassis housing  111  (see  FIG. 3 ). 
       FIGS. 4 and 5  illustrate one example cable bracket  120  configured to be utilized in the chassis system  100 . The cable bracket  120  is configured to carry one or more multi-fiber cables  190  (e.g., see  FIG. 3 ). In certain implementations, the cable bracket  120  includes a bottom member  122  and a top member  123  extending outwardly from a closure wall  121 . A hinge bracket  124  is pivotally coupled to the closure wall  121  using a hinge  125 . The hinge bracket  124  is coupled to the chassis housing  111  (e.g., at one of the sidewalls  113 ) to pivotally mount the cable bracket  120  to the chassis  110 . Accordingly, in the example shown, the cable bracket  120  is configured to pivot between a closed position and an open position. The cable bracket extends at least partially across the open rear  117  of the chassis housing  111  when in the closed position. The cable bracket  120  does not extend across the open rear  117  when in the open position. 
     The cable bracket  120  is configured to support a clamping assembly  195  to secure the cable  190  to the cable bracket  120 .  FIG. 6  illustrates one example clamping assembly  195  for holding one or more cables. The clamping assembly  195  includes one or more gasket members  196  held between two clamp members  197 . The gasket member(s)  196  is disposed around a cable  190  to be clamped. The clamp members  197  and gasket members  196  define aligned fastener apertures  198  through which a fastener can extend to hold the clamp members  197  and gasket members  196  together. Tightening the fastener increases a compressive force between the two clamp members  197 . In certain examples, one or more clamping assemblies  195  can be disposed adjacent each other so that the fastener apertures  198  align. Accordingly, a fastener can simultaneously apply a compressive force to multiple clamping assemblies  195 . 
     As shown in  FIG. 5 , the closure wall  121  of the cable bracket  120  defines first apertures  127  that are sized and positioned to align with the fastener apertures  198  of a clamping assembly  195  mounted to the cable bracket  120  (e.g., see  FIG. 8 ). Accordingly, the fastener can be inserted through the closure wall  121  (via the first apertures  127 ) in addition to the clamping assembly  195 , thereby securing the clamping assembly  195  to the closure wall  121 . In certain examples, the cable bracket  120  includes support members  126  at an opposite side of the top and bottom members  122 ,  123  from the closure wall  121 . The support members  126  also define fastener apertures  127  to receive the fasteners of the clamping assemblies  195 . The support members  126  may provide a bracing surface for a nut to hold the fasteners in position. 
     The bottom and top members  122 ,  123  of the cable bracket  120  define open ends  129  to accommodate the cable  190  and fibers  191  ( FIG. 3 ) extending from the cable bracket  120 . In particular, the cable  190  extends into the cable bracket  120  at a first of the ends  129  and fibers  191  of the cable  190  extend out of the cable bracket  120  at a second of the ends  129 . Accordingly, the first end  129  of the cable bracket  120  provides access to one of the side ports  108 ,  109  of the chassis system  100 . The cable bracket  120  also includes second apertures  128  spaced from the first apertures  127 . In certain examples, the second apertures  128  are laterally spaced along the closure wall  121  from the bottom member  122  and the top member  123  (see  FIG. 5 ). In examples, the second apertures  128  are disposed between the hinge  125  and the second open end  129  (see  FIG. 5 ). 
       FIGS. 2-4  illustrate one example bracket cover  130  configured to be utilized in the chassis system  100 . The bracket cover  130  includes a closure wall  131  that is coupled to a hinge bracket  134  via a hinge  135 . The hinge bracket  134  is coupled to the chassis housing  111  (e.g., at one of the sidewalls  113 ) to pivotally mount the bracket cover  130  to the chassis  110 . Accordingly, in the example shown, the bracket cover  130  is configured to pivot between a closed position and an open position. The bracket cover  130  extends at least partially across the open rear  117  of the chassis housing  111  when in the closed position. The bracket cover  130  does not extend across the open rear  117  when in the open position. 
     The bracket cover  130  is configured to secure to the cable bracket  120  to hold the cable bracket  120  in position. For example, the closure wall  131  includes or is coupled to a fastening section  136  that defines apertures  137  ( FIG. 4 ) that align with the second apertures  128  of the cable bracket  120  when the bracket cover  130  and cable bracket  120  are disposed in the closed positions. One or more fasteners (e.g., set screws)  138  extend through the apertures  137  and the second apertures  128  to releasably secure the bracket cover  130  to the cable bracket  120 . Loosening or removing the fasteners  138  enables the bracket cover  130  to be moved (e.g., pivoted) away from the cable bracket  120 . 
     The bracket cover  130  is configured to close one of the side ports  108 ,  109 . For example, the bracket cover  130  includes a port cover  132  that extends across one of the side ports  108 ,  109  when the bracket cover  130  is disposed in the closed position. In examples, the port cover  132  is located closer to the hinge  135  than t the apertures  137 . In certain implementations, the bracket cover  130  also includes a notch  139  or aperture that provides access to one of the side ports  108 ,  109 . In examples, the notch  139  is located at an opposite side of the closure wall  131  from the port cover  132  (see  FIG. 4 ). In an example, the apertures  137  are located at the first end  129  of the cable bracket  120  when the bracket cover  130  is coupled to the cable bracket  120  (e.g., see  FIG. 2 ). In another example, the apertures  137  are located at the second end  129  of the cable bracket  120  when the bracket cover  130  is coupled to the cable bracket  120  (e.g., see  FIG. 8 ). 
     In some implementations, the cable bracket  120  and the bracket cover  130  are symmetrical about a horizontal axis. Accordingly, each of the cable bracket  120  and the bracket cover  130  can be selectively mounted to either side  105 ,  106  of the chassis housing  111 , e.g., by flipping the piece upside down (compare  FIGS. 3 and 7 ). The cable bracket  120  and bracket cover  130  enable a user, during installation of the chassis system  100 , to select at which of the sides  105 ,  106  of the chassis system  100  the user wants to introduce the multi-fiber cable(s)  190 . The user mounts the cable bracket  120  to the selected side  105 ,  106  and mounts the bracket cover  130  to the other side  105 ,  106 . 
     In accordance with some aspects of the disclosure, the chassis  110  can be flipped upside-down to change the direction in which the open port  108 ,  109  faces without using tools. Flipping the chassis  110  causes the open port  108 ,  109  to face in the opposite direction from where it was facing. The guides  118  of the chassis  110  are structured to receive the blades  150  in a first orientation and in a second orientation that is flipped 1800 from the first orientation. Accordingly, the blades  150  can be installed in the chassis  110  when the chassis is disposed in a first orientation; the blades  150  also can be installed in the chassis  110  when the chassis  110  is disposed in a second orientation that is flipped 180° from the first orientation. 
     For example, as shown in  FIGS. 20 and 21 , the guides  118  include channels recessed into an interior surface of each sidewall  113 . In certain examples, the guide channels  118  extend between the open front  116  and the open rear  117  of the chassis  110 . In certain examples, the guide channels  118  are symmetrical about a horizontal axis. 
     When the bladed chassis system  100  is installed at a frame, the chassis  110  can be installed in either the first orientation or the second orientation based on where the cable is routed to on the frame. If the cable is routed to the first side of the frame, then the chassis  110  can be installed in the first orientation so that the open cable port faces the first side of the frame and the closed cable port faces the second side of the frame. If the cable is routed to the second side of the frame, then the chassis  110  can be installed in the second orientation so that the open cable port faces the second side of the frame and the closed cable port faces the first side of the frame. The blades  150  can be inserted into the chassis in the same orientation relative to the frame regardless of whether the chassis is mounted in the frame in the first or second orientation. As will be discussed in more detail herein, a front panel  140  can be coupled to the chassis  110  regardless of the orientation of the chassis  110 . 
       FIG. 8  illustrates another example bladed chassis system  100 ′ including a chassis  110 ′ and a blade  150 ,  160 . The bladed chassis system  100 ′ is substantially similar to the bladed chassis system  100  shown in  FIGS. 1-7  except for the design of the cable bracket  120 ′ and the bracket cover  130 ′. The cable bracket  120 ′ and the bracket cover  130 ′ are substantially the same as the cable bracket  120  and bracket cover  130  shown in  FIGS. 1-7 , except as discussed below. 
     The cable bracket  120 ′ shown in  FIG. 8  does not include support members opposite the closure wall. Furthermore, the closure wall of the cable bracket  120 ′ does not define the second apertures for receiving fasteners  138 ′ from the bracket cover  130 . Rather, retention flanges  126 ′ extend from the bottom  122 ′ member and top member of the cable bracket  120 ′. Each retention flange  126 ′ defines an aperture through which one of the fasteners  138 ′ can extend to secure the bracket cover  130 ′ to the cable bracket  120 ′. 
     The bracket cover  130 ′ shown in  FIG. 8  does not include a notch providing access to the open side port  108 ,  109 . Rather, the fastening section  136 ′ of the bracket cover  130 ′ is coplanar with the closure wall  131 ′. The fastening section  136 ′ extends across the retention flanges  126 ′ of the cable bracket  120 ′ to align the fastener apertures when the cable bracket  120 ′ and the bracket cover  130 ′ are in the closed positions. 
       FIGS. 9-11  illustrate example blades  150 ,  160  configured to mount within the interior  115  of a bladed chassis system  100 ,  100 ′. Each blade  150 ,  160  includes a base  151  having slides  152  disposed at opposite sides thereof. The slides  152  are configured to ride in the guides  118  defined in the chassis  110 . The slides  152  enable the blade  150 ,  160  to slide forwardly and rearwardly relative to the chassis  110 . Each slide  152  includes a first release  152   a  at the forward end of the blade  150 ,  160  and a second release  152   b  at the rearward end of the blade  150 . Each blade  150 ,  160  also includes a forward and rearward catch or stop  153 . Flexing the first release  152   a  releases the forward stop  153  from an interior surface of the chassis sidewalls  113 . Flexing the second release  152   b  releases the rearward stop  153  from an interior surface of the chassis sidewalls  113 . 
     A front edge  154  of the base  151  is disposed at an intermediate position along the slides  152 . A rearward edge is disposed towards the rearward end of the slides  152 . In certain examples, a flange  158  extends from a rearward edge of the base  151  of the blade  150 ,  160 . In some examples, the flange  158  defines one or more openings  159  to provide a handle for a user to withdraw the blade  150 ,  160  through the rear  117  of the chassis  110 . In other examples, the flange  158  otherwise provides a handle or handhold for the user to manipulate the blade  150 ,  160  from the rear  102  of the chassis system  100 ,  100 ′. 
     One or more support members  155  extend forwardly from the front edge  154  of the blade  150 ,  160 . An adapter mounting arrangement  170  can be mounted to the support member  155 . In certain examples, the support member  155  includes connection structures that cooperate with connection structures on the adapter mounting arrangement  170 . In the example shown, the support member  155  includes a notched end  165   a , a first aperture  165   b , a second aperture  165   c , and a pin  165   d.    
     One example adapter mounting arrangement  170  is shown in  FIG. 10 . The adapter mounting arrangement  170  extends from a first end  171  to a second end  172 . The first end  171  defines a retention section  173 . In the example shown, the retention section  173  defines a passage through which fibers or patch cables can be routed. A gap  174  may enable the fibers or patch cables to enter the passage without being threaded therethrough. In other examples, the retention section  173  can be otherwise shaped to guide the fibers or patch cables away from the front  101  of the chassis system  100  while inhibiting tangling and/or excessive bending of the fibers and/or patch cables. 
     Each adapter mounting arrangement  170  includes an adapter mount  175 . One or more adapter blocks  200 ,  205  couple to the adapter mount  175  of the adapter mounting arrangements  170 . In certain examples, a first end of each adapter block  200 ,  205  couples to an adapter mount  175  at a first adapter mount arrangement  170  and a second end of each adapter block  200 ,  205  couples to an adapter mount  175  at a second adapter mount arrangement  170 . In the example shown, the adapter mount  175  includes guide channels and a latch. In other examples, the adapter mount can include guide pins, guide apertures, or other retention structures. In the example shown, the adapter mounting arrangement  170  includes two adapter mounts  175  facing in opposite directions. 
     The adapter mounting arrangement  170  is configured to secure to the support member  155 . For example, in certain implementations, the adapter mounting arrangement  170  includes a first upwardly facing ledge  176 , a second upwardly facing ledge  177 , a downwardly extending tab  178 , and a cap  179 . The cap  179  is disposed at the second end  172  of the adapter mounting arrangement  170 . The tab  178  is disposed adjacent the cap  179 . The first ledge  176  is disposed between the first end  171  and the adapter mount  175 . The second ledge  177  is disposed between the adapter mount  175  and the tab  178 . 
     To mount the adapter mounting arrangement  170  to the support member  155  of the blade  150 ,  160 , the first ledge  176  is aligned with the notched end  156   a  of the support member  155  and the second ledge  177  is aligned with the first aperture  156   b . As the adapter mounting arrangement  170  is slid rearwardly relative to the blade  150 ,  160 , the adapter mounting arrangement  170  is rotated so that the tab  178  enters the second aperture  156   c  and the cap  179  covers the pin  156   d . The cap  179  and tab  178  hold the adapter mounting arrangement  170  from sliding forwardly to release the first and second ledges  176 ,  177 . 
     In some implementations, an example blade  160  includes a retention arm  165  that extend outwardly from the front edge  154  of the blade base  151  between two adjacent ones of the adapter mounting arrangements  170  (see  FIG. 11 ). The retention arm  165  is flat, thereby allowing an adapter block  205  to extend over the retention arm  165  between the two adapter mounting arrangements  170 . A distal end of the retention arm  165  provides a retention section  166 . In the example shown in  FIG. 11 , the retention section  166  includes a hook folded back to face the rear  102  of the bladed chassis system  100 ,  100 ′. In other implementations, an example blade  150  includes only adapter mounting arrangements  170  extending outwardly from the front edge  154  of the blade base  151  (see  FIG. 9 ). 
     In some implementations, the adapter block  200  has accessible rearwardly-facing ports for receiving the fibers  191  of the multi-fiber cable  190 . In such implementations, the adapter block  200  is sized so that the front edge  154  of the blade base  151  is spaced rearwardly from rearwardly-facing ports of the adapter block  200 . Thereby, finger access for the rearwardly-facing ports is provided (see  FIG. 9 ). In other implementations, the adapter block  205  is sized to reach or extend over the front edge  154  of the blade base  151 . In some such implementations, the adapter block  205  has sideways-facing ports for receiving the fibers  191  of the multi-fiber cable  190 . In the example shown in  FIG. 11 , the base  151  of the blade  160  defines apertures  164  and a rail  163  that accommodate the adapter block  205 . 
     In accordance with some implementations, the blades  150 ,  160  include one or more fiber management trays. Each fiber management tray  180  defines a fastener aperture that defines a rotational axis AR ( FIG. 9 ). The fiber management tray can be positioned on the blade base  151  in any selected rotational orientation and then secured to the base  151  in the selected rotational orientation by a fastener. In some examples, the blade base  151  also defines a fastener aperture for receiving the fastener. In other examples, the blade base  151  includes an upwardly extending pin  156  ( FIG. 11 ) that fits into the fastener aperture  156 . In an example, a fastener can be inserted through the fastener aperture  156  and into the pin  156 . 
       FIGS. 12 and 13  illustrate two examples of fiber management trays  180 ,  180 ′. Each fiber management tray  180 ,  180 ′ includes a spool  181  and a fanout holder  187 . The spool  181  includes a drum  182  extending upwardly from a tray base  183 . Retaining tabs  184  extend upwardly from the tray base  183  at location radially spaced from the drum  182  and circumferentially spaced from each other. In the example shown, retaining fingers  185  extend outwardly from the drum  182  and inwardly from the retaining tabs  184 . The fastener aperture  186  is defined through the drum  182 . 
     The fanout holder  187  includes at least one holding structure  189  extending upwardly from a base  188 , which is coupled to the tray base  183  of the spool  181 . In the example tray  180  shown in  FIG. 12 , the fanout holder  187  includes a single holding structure  189 . In the example tray  180 ′ shown in  FIG. 13 , the fanout holder  187 ′ includes multiple (e.g., two) holding structures  189 . In the examples shown, the holding structure  189  includes latching arms. In some of the examples shown, the holding structures include pegs. 
       FIGS. 14-19  illustrate a moveable and removable front panel  140  that extends across the open front  116  of the chassis  110 . The chassis  110  includes at least two arms  148  that extend forwardly of the open front  116  of the chassis  110  from opposite sides  105 ,  106  of the chassis  110 . The front panel  140  removably couples to distal ends of the arms  148 . In some examples, the arms  148  are located towards the top  103  of the chassis  110 . In other examples, the arms  148  are located towards the bottom  104  of the chassis  110 . In still other examples, the chassis  110  includes two arms  148  towards the top  103  and two arms  148  towards the bottom  104 . The distal ends of the arms  148  define pinot pins  149 . 
     The front panel  140  includes a wall  141  that extends from a first end  142  to a second end  143 . A mounting structure  144  is disposed at each end  142 ,  143 . As shown in  FIG. 16 , each mounting structure  144  includes at least one pin receptacle  145 . The pin receptacle  145  is configured to snap over (or otherwise connect to) the pivot pins  149  of the forwardly extending arms  148 . In certain examples, each mounting structure  144  includes two pin receptacles  145 . In such examples, the top pin receptacles  145  are configured to snap over the pivot pins  149  of the top arms  148  and the bottom pin receptacles  145  are configured to snap over the pivot pins  149  of the bottom arms  148  (see.  FIG. 16 ). 
     In accordance with some aspects of the disclosure, the front panel  140  is movable (e.g., pivotable) between a closed position ( FIG. 14 ) and a first open position ( FIG. 15 ). For example, the top pin receptacles  145  can be detached from the pivot pins  149  of the top arms  148 , thereby allowing the front panel  140  to pivot about the pivot pins  149  of the bottom arms  148 . When in the first open position, the front panel  140  is retracted sufficiently from the open front  116  to enable blades  150 ,  160  to be installed into and/or removed from the chassis  110  through the open front. In certain examples, when in the first open position, the front panel  140  is retracted sufficiently from the open front  116  to enable blades  150 ,  160  to be installed into and/or removed from any blade position within the chassis  110  through the open front. 
     In accordance with some aspects of the disclosure, the front panel  140  is movable (e.g., pivotable) to a second open position ( FIG. 17 ). For example, the bottom pin receptacles  145  can be detached from the pivot pins  149  of the bottom arms  148 , thereby allowing the front panel  140  to pivot about the pivot pins  149  of the top arms  148 . When in the second open position, the front panel  140  is retracted sufficiently from the open front  116  to enable blades  150 ,  160  to be installed into and/or removed from the chassis  110  through the open front. In certain examples, when in the second open position, the front panel  140  is retracted sufficiently from the open front  116  to enable blades  150 ,  160  to be installed into and/or removed from any blade position within the chassis  110  through the open front. 
     In certain examples, a side flange  146  extends rearwardly from each end  142 ,  143  the wall  141 . In certain examples, the wall  141  includes one or more handles  147  that aid a user in manipulating the front panel  140 . In the example shown in  FIG. 14 , the front panel  140  has a handle  147  at each end  142 ,  143 . The handles  147  extend forwardly of the wall  141 . In other examples, the wall  141  includes one or more notches  147 ′ that aid a user in manipulating the front panel  140 . In the example shown in  FIG. 19 , the front panel  140  has a notch  147 ′ at each end  142 ,  143 . 
     In certain implementations, the front panel  140  can be attached to the chassis  110  in a first orientation and in a second orientation that is flipped 1800 from the first orientation. Accordingly, the handle  147  can be selectively disposed at the top or bottom of the front panel wall  141 . In particular, the handle  147  can be selectively disposed at the top or bottom of the front panel wall  141  regardless of the orientation of the chassis  110 . For example, the front panel  140  can be coupled to the chassis  110  while the chassis  110  is disposed in a first orientation so that the handle  147  of the front panel  140  extends from a top of the wall  141 . The front panel  140  can be removed from the chassis  110 , the chassis can be flipped 180°, and the front panel  140  can be reinstalled on the chassis  110  with the handle  147  extending from the top of the wall  141 . 
       FIGS. 22-32  illustrate another example bladed chassis system  300  including a chassis  310  and at least one blade  350 ,  360 . In various implementations, the chassis  310  can hold multiple (e.g., two, three, four, five, six, eight, etc.) blades  350 ,  360 . Accordingly, the chassis  310  can be sized at 1 RU (rack unit), 2 RU, 3 RU, 4 RU, 5 RU, 6 RU, etc. The chassis system  300  has a front  301 , a rear  302 , a top  303 , a bottom  304 , a first side  305 , and a second side  306 . The chassis  310  includes a housing  311  having two sidewalls  313  extending between a first end wall  312  ( FIG. 23 ) and a second end wall  314  ( FIG. 22 ). The first end wall  312 , sidewalls  313 , and second end wall  314  define an interior  315  having an open front  316  and an open rear  317 . 
     Interior surfaces of the sidewalls  313  include guides  318  at which the blades  350 ,  360  can be received. The guides  318  define channels within which portions of the blades  350 ,  360  slide. In certain examples, the guides  318  extend between the open front  316  and the open rear  317  of the chassis  310 . In certain examples, the guides  318  are symmetrical about a horizontal axis. In certain examples, the guides  318  include hooks that extend through elongated openings defined in the sidewalls  313 . The guides  318  also define ramped shoulders at one end that inhibit sliding movement of the guides  318  when the shoulders snap into openings defined in the sidewalls  313 . In certain examples, the sidewalls  313  define an extra opening for each guide  318  through which a tool can be inserted to release the shoulders from the openings, thereby freeing the guide  318  for sliding movement to enable removal from the sidewall  313 . 
     In certain examples, a shelf  307  can be disposed within the interior  315  at an intermediate location between the first and second end walls  312 ,  314 . The shelf  307  facilitates managing the optical fibers within the interior  315 . For example, the shelf  307  helps to separate the optical fibers of blades  350 ,  360  mounted to guides  318  at the bottom of the sidewalls  313  from the optical fibers of blades  350 ,  360  mounted to guides  318  at the top of the sidewalls  313 . In certain examples, the blades  350 ,  360  are mounted to the guides  318  at the top of the sidewalls  313  first. In such implementations, the shelf  307  retains the optical fibers out of a bottom section of the chassis  310  to facilitate loading blades  350 ,  360  into the bottom section of the chassis  310 . 
     Mounting brackets  319  are disposed at exterior surfaces of the sidewalls  313 . In certain examples, a shelf bracket  319  can be mounted to the rack at which the bladed chassis system  300  is to be received. The chassis  310  can seat upon the shelf bracket  319  to provide additional support for the bladed chassis system  300 . A front panel  340  can be coupled to the chassis  310  at the open front  316 . In certain examples, the front panel  340  can pivot downwardly to expose the open front  316  of the chassis  310 . In certain examples, the front panel  340  also can pivot upwardly to expose the open front  316 . 
     As shown in  FIG. 24 , the chassis system  300  is configured to receive one or more multi-fiber cables  390  at the rear  302  of the chassis system  300 . In certain examples, the chassis system  300  defines one or more cable ports  308  at the rear  302  of the chassis system  300 . In certain implementations, the cable port(s)  308  is disposed at an intermediate location along the rear  301  of the bladed chassis system  300 . In some implementations, the cable port(s)  308  faces towards a first side  305  of the chassis  310 . In other implementations, the cable port(s)  308  faces towards a second side  306  of the chassis  310 . In certain implementations, a first cable port  308  can face towards the first side  305  while a second cable port  208  faces towards the second side  306 . As will be described in more detail herein, one or more multi-fiber cables  390  can be received and anchored at the ports  308 . 
     As shown in  FIGS. 25-28 , at least one cable bracket  320  and at least one bracket cover  330  are mounted to the chassis housing  311  at the open rear  317 . Each of the cable bracket  320  and the bracket cover  330  is movable between an open position ( FIG. 26 ) and a closed position ( FIG. 25 ). The cable brackets  320  and bracket covers  330  cooperate to close the open rear  317  when both are disposed in the closed positions (see  FIGS. 25 and 27 ). In certain implementations, the shelf  307  ( FIG. 23 ) disposed within the chassis interior  315  separates the chassis interior  315  into top and bottom sections. In some such implementations, each of the sections has a corresponding cable bracket  320  and bracket cover  330  so that only one section need be opened to obtain access to the blades  350 ,  360  of that section. In other implementations, a single bracket cover  330  can be utilized with multiple cable brackets  320 . In still other implementations, a single cable bracket  320  can be utilized with multiple bracket covers  330 . 
     The cable bracket  320  and the bracket cover  330  also cooperate to define one or more cable ports  308  when disposed in the closed positions. Moving both the cable bracket  320  and bracket cover  330  to the open positions reveals the open rear  317  sufficient to enable a blade  350 ,  360  to be inserted and/or removed at the open rear  317  of the chassis housing  311  (see  FIG. 27 ). 
       FIGS. 26 and 28  illustrate examples of a cable bracket  320  configured to be utilized in the chassis system  300 . The cable bracket  320  is configured to carry one or more multi-fiber cables  390  (e.g., see  FIGS. 24 and 27 ). In certain implementations, the cable bracket  320  includes a closure wall  321 . A hinge bracket  324  is pivotally coupled to the closure wall  321  using a hinge  325 . The hinge bracket  324  is coupled to the chassis housing  311  (e.g., at one of the sidewalls  313 ) to pivotally mount the cable bracket  320  to the chassis  310 . Accordingly, in the example shown, the cable bracket  320  is configured to pivot between a closed position and an open position. The cable bracket  320  extends at least partially across the open rear  317  of the chassis housing  311  when in the closed position. The cable bracket  320  does not extend across the open rear  317  when in the open position. 
     The cable bracket  320  is configured to support a clamping assembly  395  to secure the cable  390  to the cable bracket  320 .  FIGS. 24 and 27  illustrates example clamping assemblies  395  for holding one or more cables. As shown in  FIGS. 26 and 28 , the closure wall  321  of the cable bracket  320  defines first apertures  327  that are sized and positioned to align with fastener apertures of the clamping assemblies  395  mounted to the cable bracket  320 . Accordingly, the fastener can be inserted through the closure wall  321  (via the first apertures  327 ) in addition to the clamping assembly  395 , thereby securing the clamping assembly  395  to the closure wall  321 . 
     Additional disclosure about example suitable clamping assemblies  395  can be found in U.S. Patent Application No. 62/082,479 titled “Fiber Optic Cable with Flexible Conduit,” the disclosure of which is hereby incorporated herein by reference in its entirety. 
     In certain examples, the cable bracket  320  includes support members  326  spaced outwardly from the closure wall  321 . For example, the support members  326  can extend from a top member  322  and a bottom member  323  that extend outwardly from the closure wall  321 . In certain examples, the bottom and top members  322 ,  323  extend from the closure wall  321  at a non-perpendicular angle. The bottom and top members  322 ,  323  of the cable bracket  320  are shorter than the closure wall  321  to accommodate and provide access to the cables  390  and the cable brackets  320 . The support members  326  define second apertures  328 . 
       FIGS. 26 and 28  also illustrate examples of a bracket covers  330  configured to be utilized in the chassis system  300 . The bracket cover  330  includes a closure wall  331  that is coupled to a hinge bracket  334  via a hinge  335 . The hinge bracket  334  is coupled to the chassis housing  311  (e.g., at one of the sidewalls  313 ) to pivotally mount the bracket cover  330  to the chassis  310 . Accordingly, in the example shown, the bracket cover  330  is configured to pivot between a closed position and an open position. The bracket cover  330  extends at least partially across the open rear  317  of the chassis housing  311  when in the closed position. The bracket cover  330  does not extend across the open rear  317  when in the open position. 
     The bracket cover  330  is configured to secure to the cable bracket  320  to hold the cable bracket  320  in position. For example, the closure wall  331  includes or is coupled to a fastening section  336  ( FIGS. 25 and 27 ) that defines apertures  337  ( FIGS. 26 and 28 ) that align with the second apertures  328  of the cable bracket  320  when the bracket cover  330  and cable bracket  320  are disposed in the closed positions. One or more fasteners (e.g., set screws)  338  extend through the apertures  337  and the second apertures  328  to releasably secure the bracket cover  330  to the cable bracket  320 . Loosening or removing the fasteners  338  enables the bracket cover  330  to be moved (e.g., pivoted) away from the cable bracket  320 . 
     The cable port(s)  308  are defined by a gap between the closure wall  321  of the cable bracket  320  and the closure wall  331  of the bracket cover  330 . A top member  332  and a bottom member  333  can extend from the bracket cover closure wall  331  to the cable bracket closure wall  321 . The top and bottom members  332 ,  333  cooperate with the bracket cover closure wall  331  to protect optical fibers of the multi-fiber cables  390 . In certain examples, a flange  339  also can extend over a portion of the gap to further protect the optical fibers  390 . In the example shown, the flange  339  extends from the bracket cover closure wall  331  at a non-perpendicular angle. 
     In some implementations, the cable bracket  320  and the bracket cover  330  are symmetrical about a horizontal axis. Accordingly, each of the cable bracket  320  and the bracket cover  330  can be selectively mounted to either side  305 ,  306  of the chassis housing  311 , e.g., by flipping the piece upside down. The cable bracket  320  and bracket cover  330  enable a user, during installation of the chassis system  300 , to select from which of the sides  305 ,  306  of the chassis system  300  the user wants to introduce the multi-fiber cable(s)  390 . The user mounts the cable bracket  320  to the selected side  305 ,  306  and mounts the bracket cover  330  to the other side  305 ,  306 . Furthermore, in systems  300  utilizing multiple pairs of cable brackets  320  and bracket covers  330 , the user may select to face one of the ports  308  to the first side  305  and face another of the ports to the second side  306 . 
     In accordance with some aspects of the disclosure, the chassis  310  can be flipped upside-down to change the direction in which the port  308  faces without using tools. Flipping the chassis  310  causes the port  308  to face in the opposite direction from where it was facing. The guides  318  of the chassis  310  are structured to receive the blades  350 ,  360  in a first orientation and in a second orientation that is flipped 1800 from the first orientation. Accordingly, the blades  350 ,  360  can be installed in the chassis  310  when the chassis is disposed in a first orientation and the blades  350 ,  360  also can be installed in the chassis  310  when the chassis  310  is disposed in a second orientation that is flipped 180° from the first orientation. 
     When the bladed chassis system  300  is installed at a frame, the chassis  310  can be installed in either the first orientation or the second orientation based on where the cable is routed to on the frame. If the cable is routed to the first side of the frame, then the chassis  310  can be installed in the first orientation so that the cable port  308  faces the first side of the frame. If the cable is routed to the second side of the frame, then the chassis  310  can be installed in the second orientation so that the cable port  308  faces the second side of the frame. The blades  350 ,  360  can be inserted into the chassis in the same orientation relative to the frame regardless of whether the chassis is mounted in the frame in the first or second orientation. 
       FIGS. 29 and 30  illustrate example blades  350 ,  360  configured to mount within the interior  315  of a bladed chassis system  300 . Each blade  350 ,  360  includes a base  351  having slides  352  disposed at opposite sides thereof. The slides  352  are configured to ride in the guides  318  defined in the chassis  310 . The slides  352  enable the blade  350 ,  360  to slide forwardly and rearwardly relative to the chassis  310 . Each slide  352  includes a first release  352   a  at the forward end of the blade  350 ,  360  and a second release  352   b  at the rearward end of the blade  350 . Each blade  350 ,  360  also includes a forward and rearward catch or stop  353   a ,  353   b , respectively. Flexing the first release  352   a  releases the forward stop  353   a  from an interior surface of the chassis sidewall  313  and/or guide  318 . Flexing the second release  352   b  releases the rearward stop  353   b  from an interior surface of the chassis sidewall  313  and/or guide  318 . In certain examples, the second release  352   b  curves inwardly from the respective guide  352  and then curves back outwardly to form a finger catch portion  357 . To release the rearward stop  353   b , the user presses a finger against the finger catch portion  357  to deflect the finger catch portion  357  inwardly relative to the guide  352 . 
     A front edge  354  of the base  351  is disposed at an intermediate position along the slides  352 . A rearward edge is disposed towards the rearward end of the slides  352 . In certain examples, a flange  358  extends from a rearward edge of the base  351  of the blade  350 ,  360 . In some examples, the flange  358  defines one or more openings  359  to provide a handle for a user to withdraw the blade  350 ,  360  through the rear  317  of the chassis  310 . In other examples, the flange  358  otherwise provides a handle or handhold for the user to manipulate the blade  350 ,  360  from the rear  302  of the chassis system  300 . 
     In some implementations, the blade  350 ,  360  also includes one or more cable managers  380 . Each cable manager  380  is configured to retain one or more optical fibers at the cable manager  380 . For example, each cable manager  380  includes a bend radius limiting surface  381 , a retention member  382  extending outwardly from the bend radius limiting surface  381 , and a fiber catch  383  disposed at an opposite end of the retention member  382  from the bend radius limiting surface  381 . In certain examples, an inner surface of the fiber catch  383  defines a second bend radius limiting surface. In certain examples, an outer surface of the fiber catch  383  is contoured to facilitate sliding insertion of optical fibers into the gap provided between the retention member  382  and the base  351  of the blade  350 ,  360 . 
     One or more support members  355  extend forwardly from the front edge  354  of the blade  350 ,  360 . An adapter mounting arrangement  370  can be mounted to the support member  355 . In certain examples, the support member  355  includes connection structures that cooperate with connection structures on the adapter mounting arrangement  370 . In the example shown, the support members  355  and adapter mounting arrangements  370  are the same as the support members  155  and adapter mounting arrangements  170  of  FIGS. 9-12 . 
     In some implementations, an example blade  350  includes a retention arm  365  that extend outwardly from the front edge  354  of the blade base  351  between two adjacent ones of the adapter mounting arrangements  370  (see  FIG. 29 ). The retention arm  365  is the same as the retention arm  165  of  FIGS. 9-12 . In other implementations, an example blade  360  does not include retention arms  365 . Rather, no structure extends from the front edge  354  of the blade base  351  between the adapter mounting arrangements  370 . In certain implementations, a retention section  373  of the adapter mounting arrangement  370  can extend from components mounted to the blade  360 . For example, in one implementation, the retention section  373 , which is substantially the same as the retention section  173  of  FIGS. 9-12 , extends outwardly from an adapter block  200 , from between two adapter blocks  200 , or from a fiber optic module/cassette  400 . 
       FIGS. 30-32  illustrate one example fiber optic module/cassette  400  that is configured for use within the chassis/frame of  FIGS. 22-28 . The cassette  400  includes a number of connection locations for inputting fiber optic signals thereinto for processing. In the depicted embodiment, the connection locations are defined by fiber optic adapters  405  ( FIG. 32 ). In certain examples, the adapters may be of the MPO format so that they are configured to receive fiber optic connectors having an MPO footprint. Other styles may be used. 
     The cassette  400  includes a cassette housing generally formed by a base portion  401  that is enclosed by a cover portion  402 . The fiber optic adapters  405  can be snapped into the base portion  401  and the cover portion  402  can enclose the adapters  405 , any fiber optic devices within the cassette  400  for processing the input signals, and any cabling therein. 
     In the depicted embodiment, the MPO type adapters  405  are positioned at a front of the cassette  400  and are used to both input and output fiber optic signals via cables terminated with connectors. As shown, the adapters  405  are configured to be snap-fit to the base portion  401  of the cassette  400  via flexible cantilever tabs  403  ( FIG. 32 ). Other fixation methods may be used. In other implementations, the signal input locations (or output locations) may be at different locations on the cassette such as at the rear of the cassette. 
     As shown in  FIG. 32 , the cassette  400  may include spools  404  defining cable retainers  406  for managing cables within the cassette housing  400 . In some implementations, the cable retainers  406  extend from an opposite side of the spools  404  from the base  401 . In other implementations, the cable retainers  406  can extend from intermediate positions along the spools  404 . 
     The optical equipment housed within the cassette  400  for processing the signals may include a variety of equipment. For example, the housed equipment may be fiber optic splitters, combiners, multiplexer/demultiplexers, filters, etc. The cassettes  400  may also include splices  407  for simply splicing input cables to cables that are within the cassette  400  that have been terminated with connectors leading to the front adapters  405 . These connectors may mate with outside connectors via the adapters  405 . 
     As noted above, the adapter mounting arrangements  370  of the blades  350 ,  360  have retention sections  373  that support the cables extending forwardly of the blades  350 ,  360 . The retention sections  373  help support cables as they extend from the blades  350 ,  360  to the right and/or left sides of the chassis  310 . However, when larger sized cassettes  400  are used with the blades  360  (e.g., as shown in  FIG. 30 ), cables extending from the adapters  405  to the retention sections  373  may still experience some sagging or tangling due to the large distances between the connection points and the retention sections  373  of the blades  360 . 
     For this reason, the cassettes  400  may be configured with their own cable managers  408  that provide support at the center point of the cassettes  400  to limit sagging or tangling as the cables are lead from the connection points to the retention sections  373  of the blades  360 . In the example shown, the cable managers  408  have substantially the same structure as the retention sections  373  of the adapter mounting arrangements  370 . In certain examples, the cable managers  408  also can include adapter mount structures (e.g., adapter mount structures  175 ) of the adapter mounting arrangements  170 ,  370 . 
     According to one example version, the cassette cable manager  408  may be removable mounted to the cassette  400  via snap-fit interlocks. In the depicted version, the cable manager  408  is snap-fit to the base portion  401  of the cassette  400  via flexible cantilever tabs  409  (similar to those used for the adapters  405 ). In certain examples, the cassette cable manager  408  also defines tabs that are used in snap-fitting the cover portion  402  to the base portion  401 . 
       FIGS. 33 and 34  illustrate an example hinge arrangement  460  that couples an example front panel  450  to an example chassis. In the example shown, the chassis is a 1 RU chassis. In other implementations, the chassis  310  can be any desired size (e.g., 2 RU, 3 RU, 4 RU, 5 RU, 6 RU, etc.). The front panel  450  is configured to extend across an open front of the chassis. In the example shown, the front panel  450  is configured to pivot downwardly from a closed position to an open position to provide access to the blades within the chassis from the front of the chassis. 
     The hinge arrangement  460  includes a door arrangement  460 , an elongated pivot member  465 , a support member  455  and an attachment member  458 . The support member  455  and the attachment member  458  are mounted to the chassis at the top and bottom of the front opening, respectively. The door arrangement  460  mounts to the front panel  450 . The elongated pivot member  465  mounts the door arrangement  460  to the support member  455 . The front panel  450  pivots about an axis defined by the support member  455  and/or the elongated pivot member  465 . 
     The door arrangement  460  includes a body  461  having a pin  462  at a first end and defining a passage  463  towards an opposite second end. The attachment member  458  defines an open-ended recess  459  sized to receive the pin  462  of the door arrangement  460 . Engagement between the attachment member  458  and the pin  462  holds the front panel  450  in the closed position relative to the chassis. The open-ended channel  459  is configured to allow the pin  462  to be snapped in and out of the channel  459 . 
     The elongated pivot member  465  extends from a first end to a second end. The first end includes a first pivot pin  466  that extends through the passage  463  of the door arrangement body  461 . The second end of the elongated pivot member  465  defines an opening  468 . In certain examples, the pivot member  465  bends or otherwise defines a contour between the first and second ends. In the example shown, the elongated pivot member  465  has an L-shape. 
     The support member  455  includes a second pin  456  configured to extend through the opening  468  in the pivot member  465 . In certain examples, the second pin  456  may have a curved end  457  that aids in retaining the pivot member  465  on the second pin  456 . As the front panel  450  moves between the open and closed positions, the second end of the pivot member  465  pivots about the second pin  456  and the front panel  450  pivots about the first pivot pin  466 . 
     In other implementations, the support member  455  can disposed at the top of the open front and the attachment member  458  can be disposed at the bottom of the open front to enable the front panel  450  to pivot upwardly to the open position. 
       FIGS. 35-47  illustrate example implementations of latching assemblies suitable for use on any blade  150 ,  160 ,  350 ,  360 ,  550  to allow the blade  150 ,  160 ,  350 ,  360 ,  550  to move relative to the chassis system  100 ,  100 ′,  300 . Each latching assembly includes a latching arrangement that couples to one side of the blade  150 ,  160 ,  350 ,  360 ,  550  and a guide member that couples to one sidewall of the chassis housing  111 ,  311 . Typically, each chassis sidewall supports a guide member and each side of the blade  150 ,  160 ,  350 ,  360 ,  550  supports a latching arrangement. 
     In certain implementations, the blade  150 ,  160 ,  350 ,  360 ,  550  is removable from the chassis housing  111 ,  311  through the front. In certain implementations, the blade  150 ,  160 ,  350 ,  360 ,  550  is removable from the chassis housing  111 ,  311  through the rear. In certain implementations, a user can choose whether to remove the blade  150 ,  160 ,  350 ,  360 ,  550  from the chassis housing  111 ,  311  through the front or through the rear. 
     In systems utilizing either of the latching assemblies, the blade  150 ,  160 ,  350 ,  360 ,  550  is movable relative to the chassis housing  111 ,  311  between an operation position, a connector access position, and an adapter access position. In an example, the connector access position is located forwardly of the operation position, and the adapter access position is located forwardly of the connector access position. In certain implementations, the blade  150 ,  160 ,  350 ,  360 ,  550  is movable relative to the chassis housing  111 ,  311  to a discrete position rearward of the operation position. As the term is used herein, a “discrete” position indicates a position at which the user receives some type of feedback (e.g., tactile feedback, audible feedback, etc.) that the blade  150 ,  160 ,  350 ,  360 ,  550  has reached a predetermined position relative to the chassis. 
     In certain implementations, the latching assemblies are configured to lock the blade  150 ,  160 ,  350 ,  360 ,  550  in one or more of the discrete positions. As the term is used herein, a blade  150 ,  160 ,  350 ,  360 ,  550  is “locked” in position if the user must take affirmative steps beyond applying forward/rearward pressure to the blade  150 ,  160 ,  350 ,  360 ,  550  to move the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis  111 ,  311 . 
     In certain implementations, the latching assemblies are configured to lock the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis in the operation position. In certain implementations, the latching assemblies are configured to lock the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis in the connector access position. In certain implementations, the latching assemblies are configured to lock the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis in the operation position and in the adapter access position. In certain implementations, the latching assemblies are configured to lock the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis in the adapter access position. In certain implementations, the latching assemblies are configured to lock the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis in any discrete position. 
       FIGS. 35-42  illustrate a first example latching assembly including an example latching arrangement  520  and an example guide member  500 . The latching arrangements  520  and guide members  500  interact with each other to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to move between an operating position and a connector access position in which the blade  150 ,  160 ,  350 ,  360 ,  550  is disposed forwardly relative to the chassis housing  111 ,  311 . In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to move forward of the connector access position to an adapter access position. In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to be locked in one or more of the operation position, the connector access position, and the adapter access position. 
     In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to be removed from the chassis housing  111 ,  311  through a front of the chassis housing  111 ,  311 . For example, the blade  150 ,  160 ,  350 ,  360 ,  550  can be slid forward from the adapter access position until the blade  150 ,  160 ,  350 ,  360 ,  550  disconnects from the chassis housing  111 ,  311 . In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to be removed from the chassis housing  111 ,  311  through a rear of the chassis housing  111 ,  311 . For example, the blade  150 ,  160 ,  350 ,  360 ,  550  can be slid rearward from the operation position until the blade  150 ,  160 ,  350 ,  360 ,  550  disconnects from the chassis housing  111 ,  311 . 
       FIGS. 36-37  illustrate an example guide member  500  extending between a front  501  and a rear  502 . The guide member  500  has an inner surface  503  through which one or more channels  504  are defined. The channels  504  are elongated between the front  501  and rear  502  of the inner surface  503 . Each channel  504  is sized to receive the slide  520  of one blade  150 ,  160 ,  350 ,  360 ,  550 . In the example shown, the guide member  500  defines three channels  504 . Accordingly, the guide member  500  is configured to hold and guide three blades  150 ,  160 ,  350 ,  360 ,  550  when mounted to a chassis sidewall. In other examples, the guide member  500  can define a greater or lesser number of channels  504  (e.g., one channel, two channels, four channels, eight channels, etc.). 
     A forward end  505  of each channel  504  is open to the front  501  of the chassis housing. In some implementations, the forward end  505  is ramped or curved relative to the inner surface  503  to guide the blade slide  520  into/out of the channel  504  from the front  501  of the guide member  500 . In other implementations, the forward end  505  of each channel  504  is open to the front without tapering. In some implementations, a rearward end  506  of each channel  504  is ramped or curved relative to the inner surface  503  to guide the blade slide  520  into/out of the channel  504  from the rear  502  of the guide member  500 . In other implementations, the rearward end  506  of each channel  504  is open to the rear of the chassis housing without tapering. 
     A notch  507  is defined in the inner surface  503  at a stop location along the channel  504 . In the example shown, the notch  507  is disposed towards the forward end  505  of the channel  504 . For example, the ramp or taper at the forward end  505  may extend between the notch  507  and the front  501  of the guide member  500 . In the example shown, the notch  507  extends through the inner surface  503  above and below the channel  504 . In other examples, the notch  507  may be defined only above or only below the channel  504 . A forward portion of the notch  507  defines a rearward facing shoulder  508 . A rearward portion of the notch  507  defines a forward facing shoulder  509 . In other implementations, however, the forward portion and/or rearward portion may define a cam path ramping from the channel  504  to the inner surface  503 . 
     A trough  510  is recessed into each channel  504  along a portion of the channel  504 . The trough  510  extends from a forward end  511  to a rearward end  512 . The forward end  511  of the trough  510  is recessed rearwardly from the forward end  505  of the channel  504 . The rearward end  512  of the trough  510  is recessed forwardly from the rearward end  506  of the channel  504 . In some implementations, the forward end  511  of the trough  510  defines a rearward facing shoulder and the rearward end  512  of the trough  510  defines a cam path from the trough  510  to the channel  504 . In other implementations, however, the forward end  511  may define a cam path and/or the rearward end  512  may define a forward facing shoulder. 
       FIGS. 38-42  illustrate an example latching arrangement  520  suitable for riding along the guide member  500 . The latching arrangement  520  includes a body  523  that extends between a front end  521  and a rear end  522 . The body  523  includes a slide  524  that is sized and shaped to ride along the channel  504  of the guide member  500 . The body  523  also includes at least one forward stop member  525  and at least one rearward stop member  526 . In certain implementations, the forward stop member  525  does not extend laterally outwardly beyond the slide  524  and the rearward stop member  526  extends laterally outwardly beyond the slide  526  (see  FIG. 38 ). In certain examples, the body  523  includes two forward stop members above and below the slide  524 . In certain examples, the rearward stop member  526  extends outwardly from a middle location (between top and bottom) of the slide  504  towards the rear of the slide  504 . 
     The body  523  also includes a forward handle  527  that is configured to deflect laterally inwardly relative to the blade  150 ,  160 ,  350 ,  360 ,  550 . In the example shown, deflecting the forward handle  527  laterally inwardly causes the forward stop members  525  to move towards the blade  150 ,  160 ,  350 ,  360 ,  550 . The body  523  also includes a rearward handle  528  that is configured to deflect laterally inwardly relative to the blade  150 ,  160 ,  350 ,  360 ,  550 . Deflecting the rearward handle  528  laterally inwardly causes the rearward stop members  526  to move towards the blade  150 ,  160 ,  350 ,  360 ,  550 . 
     A leaf spring  530  is coupled to the blade  150 ,  160 ,  350 ,  360 ,  550  to strengthen the forward handle  527 . The leaf spring  530  has a mounting portion  531  that couples to the blade  150 ,  160 ,  350 ,  360 ,  550 . In certain implementations, the leaf spring  530  also has a first end  532  that inhibits laterally inward deformation over time of the forward handle  527 . For example, the leaf spring  530  may counteract the effects of material deformation within the forward handle  527  that otherwise would have allowed the undeflected position of the forward handle  527  to creep inwardly over time. In certain implementations, the first end  532  applies a force to the forward handle  527  at a location offset from the forward stop member  525 . 
     In some implementations, a latch member  540  also is coupled to the blade  150 ,  160 ,  350 ,  360 ,  550 . The latch member  540  includes a latch body  541  that is coupled to the blade  150 ,  160 ,  350 ,  360 ,  550  at a pivot location  542 . The latch body  541  is elongated between a forward end and a rearward end. The forward and rearward ends pivot relative to the blade  150 ,  160 ,  350 ,  360 ,  550  about the pivot location  542 . The forward end of the latch body  541  defines a handle  543 . The rearward end of the latch body  541  includes a stop member  544 . When the handle  543  is deflected laterally outwardly, the stop member  544  deflects laterally inwardly. 
     In certain implementations, the leaf spring  530  is configured to bias the stop member  544  of the latch member  540  laterally outwardly (see  FIGS. 39 and 40 ). Laterally outward deflection of the latch handle  543  causes laterally inward deflection of the stop member  544  (see  FIGS. 41 and 42 ). In certain examples, the leaf spring  530  has a second end  533  that engages the latch body  541  rearward of the pivot location  542 . In certain examples, the second end  533  of the leaf spring  530  is opposite the first end  532 . In certain implementations, the leaf spring  530  is curved between the first and second ends  532 ,  533 . 
     In use, when the blade  150 ,  160 ,  350 ,  360 ,  550  is disposed in the operation position relative to the chassis  111 ,  311 , the slide  524  of each latch arrangement  520  is disposed in the channel  504  of a respective guide member  500 . The forward stop member(s)  525  are disposed in the notch  507  at the forward end  505  of the channel  504 . The rearward stop member  526  is disposed at the rearward end  512  of the trough  510  defined in the channel  504 . Engagement between the forward stop member(s)  525  and the rearward facing shoulders  508  at the notch  507  inhibit forward movement of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis housing  111 ,  311 . Engagement between the rearward stop member  526  and the forward facing shoulder at the rearward end  512  inhibits rearward movement of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis housing  111 ,  311 . In certain examples, engagement between the forward stop member(s)  525  and the forward facing shoulder  509  at the notch  507  inhibit rearward movement of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis housing  111 ,  311 . The stop member  544  of the latch member  540  is deflected inwardly through engagement with the interior surface  503  of the guide member  500 . 
     To move the blade  150 ,  160 ,  350 ,  360 ,  550  forwardly to the connector access position, a user deflects the forward handle  527  of the latching arrangement  520 , which retracts the forward stop member(s)  525  from the guide member notch  507 . Retracting the forward stop member(s)  525  frees the blade  150 ,  160 ,  350 ,  360 ,  550  for forward movement. As the blade  150 ,  160 ,  350 ,  360 ,  550  moves forwardly, the slide  504  glides through the channel  504  and the rearward stop member  526  slides along the trough  510 . When the blade  150 ,  160 ,  350 ,  360 ,  550  reaches the connector access position, the stop member  544  of the latch member  540  snaps into the notch  507 . Engagement between the stop member  544  and the rearward facing shoulders  508  at the notch  507  inhibit forward movement of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis housing  111 ,  311 . In certain implementations, engagement between the stop member  544  and the forward facing shoulder  509  at the notch  507  inhibit rearward movement of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis housing  111 ,  311 . 
     To move the blade  150 ,  160 ,  350 ,  360 ,  550  from the connector access position, the user deflects the handle  543  of the latch member  540  ( FIG. 41 ) to retract the stop member  544  from the notch  507  ( FIG. 42 ). When the stop member  544  is retracted from the notch  507 , the blade  150 ,  160 ,  350 ,  360 ,  550  is free to move either forwardly to the adapter access position or rearwardly to the operation position. When the blade  150 ,  160 ,  350 ,  360 ,  550  reaches the adapter access position, the rear stop member  526  engages the forward end  511  of the trough  510 . In certain implementations, the engagement between the rear stop member  526  and the forward end  511  provide tactile feedback to the user that the blade  150 ,  160 ,  350 ,  360 ,  550  has reached a discrete position. 
     In certain implementations, the rear stop member  526  has a forward ramped surface configured to ride out of trough  510  when sufficient forward force is applied to the blade  150 ,  160 ,  350 ,  360 ,  550 . Accordingly, in such implementations, the blade  150 ,  160 ,  350 ,  360 ,  550  can be pulled forwardly out of the chassis from the adapter access position by applying a forward removal force to the blade. In certain implementations, the blade  150 ,  160 ,  350 ,  360 ,  550  can be returned to the connector access position by applying a rearward force to the blade  150 ,  160 ,  350 ,  360 ,  550 . 
     To remove the blade  150 ,  160 ,  350 ,  360 ,  550  from the chassis through the rear of the chassis, a user deflects the rearward handle  528  of the latching arrangement  520 , which retracts the rearward stop member(s)  526  from the rear end  512  of the trough  5510 . Retracting the rearward stop member(s)  526  frees the blade  150 ,  160 ,  350 ,  360 ,  550  for rearward movement. As the blade  150 ,  160 ,  350 ,  360 ,  550  moves rearwardly, the slide  504  glides through the channel  504  and the forward stop member  525  slides along the interior surface  503  of the guide member  500 . 
       FIGS. 43-47  illustrate another example implementation of a latching assembly suitable for use on any of the blades  150 ,  160 ,  350 ,  360 ,  550  and chassis systems disclosed herein. The latching assembly includes an example latching arrangement  620  and an example guide member  600 . The latching arrangements  620  and guide members  600  interact with each other to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to move between an operating position and a connector access position in which the blade  150 ,  160 ,  350 ,  360 ,  550  is disposed forwardly of the operating position. In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to move forward of the connector access position to an adapter access position. In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to be locked in one or more of the operation position, the connector access position, and the adapter access position. 
     In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to be removed from the chassis housing  111 ,  311  through a front of the chassis housing  111 ,  311 . For example, the blade  150 ,  160 ,  350 ,  360 ,  550  can be slid forward from the adapter access position until the blade  150 ,  160 ,  350 ,  360 ,  550  disconnects from the chassis housing  111 ,  311 . In certain examples, a front portion of the latching arrangement  520  must be accessed to remove the blade  150 ,  160 ,  350 ,  360 ,  550  from the chassis through the front of the chassis. In certain implementations, the latching arrangements  520  and guide members  500  interact to enable the blade  150 ,  160 ,  350 ,  360 ,  550  to be removed from the chassis housing  111 ,  311  through a rear of the chassis housing  111 ,  311 . For example, the blade  150 ,  160 ,  350 ,  360 ,  550  can be slid rearward from the operation position until the blade  150 ,  160 ,  350 ,  360 ,  550  disconnects from the chassis housing  111 ,  311 . In certain examples, a rear portion of the latching arrangement  520  must be accessed to remove the blade  150 ,  160 ,  350 ,  360 ,  550  from the chassis through the rear of the chassis. 
       FIG. 44  illustrates an example guide member  600  extending between a front  601  and a rear  602 . The guide member  600  is configured to be secured to a sidewall of the chassis. In certain implementations, the guide member  600  does not move relative to the chassis. In certain implementations, the guide member  600  includes a rail configured to glide within a channel defined by the latching arrangement  620  (e.g., see  FIG. 43 ). 
     The guide member  600  has an inner surface  603  in which one or more recessed troughs  604  are defined. In the example shown, a first trough  604  extends rearwardly from a pocket  605  to a rearward end  606 . In certain implementations, the pocket  605  defines a rearward facing shoulder. In certain implementations, the rearward end  607  of the trough  610  defines a forward facing shoulder. In certain implementations, the pocket  605  is taller than the trough  604 . For example, the pocket  605  may extend outwardly beyond a top and bottom of the trough  604  (see  FIG. 44 ). In certain implementations, cam paths  606  ramp from the interior surface  603  above and below the trough  604  down into the pocket  605  (see  FIG. 44 ). 
     In some examples, a second trough  608  is defined in the inner surface  603  rearward of the first trough  604 . In examples, the second trough  608  is aligned with and spaced rearwardly from the first trough  604 . The second trough  608  is open at the rear. In certain implementations, the second trough  608  is ramped or tapered at the front. In certain examples, the forward end of the guide member  600  defines a ramped portion  609 . In certain implementations, an additional pocket can be disposed in the inner surface  603  forward of the first trough  610 . 
       FIGS. 45-47  illustrate an example latching arrangement  620  suitable for sliding along the guide member  600 . The latching arrangement  620  extends between a front end  621  and a rear end  622 . The latching arrangement  620  includes a body  623  that supports a first handle  630 , a second handle  640 , and one or more stop members. As shown in  FIG. 45 , the body  623  can include a first body member  623   a  and a second body member  623   b  that sandwich the handles  630 ,  640  and stop members  652 ,  654 ,  656  therebetween. The first handle  630  extends forwardly of the body  623 . The first handle  630  defines a grip portion  633  that is accessible from the front  621  of the latching arrangement  620 . The second handle  640  extends rearwardly of the body  623 . The second handle  640  defines a grip portion  643  that is accessible from the rear  622  of the latching arrangement  620 . 
     Each handle  630 ,  640  is movable forwardly and rearwardly along a respective travel distance relative to the body  623 . For example, each handle  630 ,  640  may be forwardly movable from a starting position along a forward travel distance and rearwardly movable from the starting position along a rearward travel distance. The first handle  630  is separate from the second handle  640  so that forward movement of the first handle  630  does not affect the second handle  640  and rearward movement of the second handle  640  does not affect the first handle  630 . The handles  630 ,  640  are separated by a gap G ( FIG. 45 ). Rearward movement of the first handle  630  causes the first handle  630  to cross the gap G and then to move the second handle  640  rearwardly over a portion of the second handle&#39;s rearward travel distance. Forward movement of the second handle  640  causes the second handle  640  to cross the gap G and then to move the first handle  630  forwardly over a portion of the first handle&#39;s forward travel distance. 
     In the example shown, the latching arrangement  620  includes a first stop member  652 , a second stop member  654 , and a third stop member  656 . In other implementations, the latching arrangement  620  can include a greater or lesser number of stop members. Each stop member  562 ,  564 ,  566  is movable relative to the body  623  between an extended position and a retracted position. When in the extended position, the stop member  652 ,  654 ,  656  extends beyond the body  623  towards the guide member  600 . In certain implementations, the first stop member  652  defines a rearwardly facing ramp surface  653  and the second stop member  654  defines a forwardly facing ramp surface  655 . In the example shown, the first stop member  652  is taller than the second and third stop members  654 ,  656 . 
     In some implementations, the body  623  can define a first stop member mounting location  626 , a second stop member mounting location  627 , and a third stop member mounting location  628 . The stop member mounting locations  626 ,  627 ,  628  are configured to guide the movement of the stop members  652 ,  654 ,  656  between the retracted and extended positions. For example, in certain implementations, the stop member mounting locations  626 ,  627 ,  628  are configured to maintain linear movement of the stop members  652 ,  654 ,  656 . In an example, one or more of the stop member mounting locations  626 ,  627 ,  628  define grooves along which the stop members  652 ,  654 ,  656  glide. 
     Movement of the first and second handles  630 ,  640  moves the stop members  652 ,  654 ,  656  between extended and retracted positions. In some implementations, one or more of the stop members  652 ,  654 ,  656  are spring-biased to the extended position. The body  623  includes one or more walls  629  against which the handles  630 ,  640  are disposed. The walls  629  retain the handles  630 ,  640  within the body against the bias of the one or more springs. Each handle  630 ,  640  defines an opening  634 ,  644 ,  646  through which a respective one of the stop members  652 ,  654 ,  656  protrudes when in the extended position. The openings  634 ,  644 ,  646  are sufficiently wide to accommodate relative movement between the handles  630 ,  640  and the stop members  652 ,  654 ,  656 . 
     In some implementations, the first and second stop members  652 ,  654  are spring-biased to the extended position. Movement of the handles  630 ,  640  retracts the respective stop members  652 ,  654 . Each handle  630 ,  640  defines a cam path  635 ,  645  along which a portion of the respective stop member  652 ,  654  rides when the handle  630 ,  640  is moved. For example, as shown in  FIG. 46 , each cam path  635 ,  645  may define an outer ramp  635   a ,  645   a  and an inner ramp  635   b ,  645   b . A spring biases the first and second stop members  652 ,  654  to starting positions SP 1 , SP 2  along the cam path  635 ,  645 . 
     When the first handle  630  is pulled forwardly (e.g. using grip portion  633 ), a portion of the first stop member  652  rides over the inner ramp  635   a  of the first handle  630  from the starting position SP 1  to retract the first top member  652 . Forward movement of the first handle  630  does not affect the second handle  640  and, accordingly, does not affect the second or third stop members  654 ,  656 . When the second handle  640  is pulled rearwardly (e.g., using grip portion  643 ), a portion of the second stop member  654  rides over the inner ramp  645   a  of the second handle  640  from the starting position SP 2  to retract the second top member  654 . Rearward movement of the second handle  640  does not affect the first handle  630  and, accordingly, does not affect the first stop member  652 . 
     When the first handle  630  is pushed rearwardly, the first handle  630  travels across a gap G ( FIG. 45 ) to engage the second handle  640 . Continued rearward movement of the first handle  630  moves the second handle  640  rearwardly. As the first handle  630  is moved rearwardly, the portion of the first stop member  652  rides over the outer ramp  635   b  of the cam path  635  from the starting position SP 1  to retract the first stop member  652 . Due to the travel across the gap G, the second handle  640  is moved less than its full rearward travel distance. Accordingly, the second stop member  654  rides only part of the way along the outer ramp  645   b  and is only partially retracted. 
     Likewise, when the second handle  640  is pushed forwardly, the second handle  640  travels across a gap G ( FIG. 45 ) to engage the first handle  630  and then moves the first handle  630  forwardly. As the second handle  640  is moved rearwardly, the portion of the second stop member  654  rides over the outer ramp  645   b  of the cam path  645  from the starting position SP 2  to retract the second stop member  654 . Due to the travel across the gap G, the first handle  630  is moved less than its full forward travel distance. Accordingly, the first stop member  652  rides only part of the way along the outer ramp  635   b  and is only partially retracted. 
     In certain implementations, the third stop member  656  is not spring biased. In certain examples, the third stop member  656  includes a peg  657  that slides along a track  647  defined by the second handle  640 . The track  647  has a first section  647   a  and a second section  647   b  connected by a short transition section. When the peg  657  is disposed in the first section  647   a  of the track  647 , the third stop member  656  is retracted. When the peg  657  is disposed in the second section  647   b  of the track  647 , the third stop member  656  is extended. When the second handle  640  is disposed in the start position (i.e., the second stop member  654  is disposed in the start position SP 2 ), the peg  657  is disposed in the first track  647   a . Rearward movement of the second handle  640  moves the peg  657  into the second section  647   b . The rearward movement sufficient to move the peg  657  to the second section  647   b  of the track  647  is sufficient to only partially retract the second stop member  654 . 
     In use, when the blade  150 ,  160 ,  350 ,  360 ,  550  is disposed in the operation position relative to the chassis  111 ,  311 , the first stop member  652  is biased (e.g., by a coil spring) to extend into the pocket  605  defined in the guide member  600 . Engagement between the first stop member  652  and a forward edge of the pocket  605  inhibits forward motion of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis. The second stop member  654  is biased (e.g., by a coil spring) to extend into the rearward end  607  of the trough  604 . Engagement between the second stop member  654  and the forwardly facing shoulder at the rearward end  607  inhibits rearward movement of the blade  150 ,  160 ,  350 ,  360 ,  550 . The third stop member remains in the retracted position. 
     To remove the blade  150 ,  160 ,  350 ,  360 ,  550  from the chassis through the rear of the chassis, the user pulls the grip portion  643  of the second handle  640  to move the second handle  640  rearwardly. Rearward movement of the second handle  640  retracts the second stop member  654 , thereby allowing the second stop member  654  to clear the rearward edge  607  of the trough  604 . Rearward movement of the second handle  640  also extends the third stop member  656  into the second trough  608 . As the blade  150 ,  160 ,  350 ,  360 ,  550  is pulled rearwardly, the third stop member  656  glides along the second trough  608  and the second stop member  654  glides initially along an interior surface  603  of the guide member  600  and subsequently along the second trough  608 . The first stop member  652  is sufficiently tall to align with the ramp  606  at the pocket  605 . Accordingly, forward motion of the blade  150 ,  160 ,  350 ,  360 ,  550  causes the first stop member  652  to ride up the ramps  606  to retract the first stop member  652 . The first stop member  652  then rides along the inner guide surface  603  until reaching the rear end of the guide member  600 . 
     Alternatively, to move the blade  150 ,  160 ,  350 ,  360 ,  550  forwardly from the operation position to the connector access position, a user pulls the grip portion  633  of the first handle  630  to move the first handle  630  forwardly. Forward movement of the first handle  630  retracts the first stop member  652  from the pocket  605 , thereby allowing forward movement of the blade  150 ,  160 ,  350 ,  360 ,  550 . The second stop member  654  rides in the trough  604  until the seconds top member  654  reaches the pocket  605 . Engagement between the second stop member  654  and the forward edge of the pocket  605  inhibits forward motion of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis. 
     Releasing the first handle  630  allows the spring of the first stop member  652  to bias the first handle  630  to a starting position, which extends the first stop member  652 . In some implementations, the first stop member  652  engages a forward edge of the guide member  600  to inhibit rearward movement of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis. In other implementations, the first stop member  652  extends into a second pocket (not shown), which is defined by the guide member  600  forward of the pocket  605 , to inhibit rearward movement of the blade  150 ,  160 ,  350 ,  360 ,  550 . Releasing the first handle  630  does not affect the second handle  640 . 
     To move the blade  150 ,  160 ,  350 ,  360 ,  550  forwardly from the connector access position to the adapter access position, the user pushes rearwardly on the first handle  630 . While the first handle  630  is depressed rearwardly, the user pulls the blade  150 ,  160 ,  350 ,  360 ,  550  forwardly. To facilitate these steps, the body  623  of the latching arrangement  620  defines a finger notch  624  that the user can grasp while depressing the first handle  630 . The user squeezes the grip portion  633  of the first handle  630  and the finger notch  624  to effect the forward motion of the blade  150 ,  160 ,  350 ,  360 ,  550  while pushing the first handle  630  rearwardly. 
     Moving the first handle  630  rearwardly retracts the first stop member  652 . Moving the first handle  630  rearwardly also pushes the second handle  640  rearwardly along a partial rearward travel distance. Accordingly, the second stop member  654  is partially retracted and the third stop member  656  is extended. Partially retracting the second stop member  654  enables the second stop member  654  to cam out of the pocket  605  upon forward movement of the blade  150 ,  160 ,  350 ,  360 ,  550 . For example, forward ramp surface  655  of the second stop member  654  aids in camming the second stop member  654  out of the pocket  605 . The third stop member  656  glides along the trough  604  until reaching the pocket  605 . Engagement between the third stop member  656  and the forward edge of the pocket  605  inhibits forward motion of the blade  150 ,  160 ,  350 ,  360 ,  550  relative to the chassis. 
     Releasing the first handle  630  allows the spring of the first stop member  652  to bias the first handle  630  to a starting position and allows the spring of the second stop member  654  to bias the second handle  640  to the starting position. Accordingly, the third stop member  656  is retracted, thereby freeing the blade  150 ,  160 ,  350 ,  360 ,  550  for forward movement. Thereby, the blade  150 ,  160 ,  350 ,  360 ,  550  can be removed from the chassis through the front of the chassis. 
     To move the blade  150 ,  160 ,  350 ,  360 ,  550  rearwardly from the adapter access position to the connector access position, the user pushes rearwardly on the blade  150 ,  160 ,  350 ,  360 ,  550 . The third stop member  656  will remain retracted. The second stop member  654  will ride along the interior guide surface  603 . If the second stop member  654  is disposed forward of the guide  600  when in the adapter access position, then the ramp  609  will cam the second stop member  654  into a retracted position to enable the second stop member  654  to ride over the interior guide surface  603 . Upon reaching the connector access position, the second stop member  654  will be biased into the pocket  605 . 
     To move the blade  150 ,  160 ,  350 ,  360 ,  550  rearwardly from the connector access position to the operation position, the user pushes forwardly on the first handle  630 , thereby retracting the first stop member  652  out of engagement with the guide member  600  (e.g., the front edge or the second pocket). The first stop member  652  can glide along the interior guide surface  603  until reaching the first pocket  605 . The second stop member  654  glides along the trough  604  until reaching the rear end  607 . Since the stop member  654  is spring biased outwardly, the second stop member  654  will engage the forwardly facing shoulder at the rear end  607  of the trough  604  to stop the tray at the operation position. 
     In certain implementations, even if the user pushes the first handle  630  rearwardly when moving the blade  150 ,  160 ,  350 ,  360 ,  550  rearwardly, the blade  150 ,  160 ,  350 ,  360 ,  550  will stop in the operation position. Due to the gap, moving the first handle  630  rearwardly moves the second handle  640  only a portion of the rearward travel distance. Accordingly, the second stop member  654  is only partially retracted. The rearward edge of the second stop member  654  is not ramped. Accordingly, partially retracting the second stop member  654  is not sufficient to allow the second stop member  654  to clear the rear end  607  of the trough  604 . 
     The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.