Abstract:
EAS marker, in one embodiment, comprises a self-lockable loop fastener. The self-lockable loop fastener comprises an elongated strap having a first end and a second end, the second end being provided with a plurality of teeth. The self-lockable loop fastener also comprises a paddle disposed at the first end of the strap. The paddle includes a recess and a locking head. The second end of the strap is insertable into, but not through, the locking head, the locking head having a tang for lockably engaging the teeth in such a way as to prevent withdrawal of the strap from the locking head and thereby forming a locked loop of fixed size. The EAS marker also includes a resonator disposed within the recess of the paddle for emitting, when armed, a response signal in response to an interrogation signal transmitted by an EAS system, a biasing element disposed within the recess and positioned relative to the resonator so that, when the biasing element is magnetized, the resonator is armed; a separator disposed within the recess between the resonator and the biasing element for physically separating the resonator and the biasing element; and a cover secured to the paddle to encapsulate the resonator, the separator and the biasing element within the recess and to prevent access to and tampering with the tang and the locking head.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No. 60/215,088, filed Jun. 29, 2000, and of U.S. Provisional Patent Application Ser. No. 60/230,771, filed Sep. 7, 2000, both of which are incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   The present invention relates generally to electronic article surveillance (EAS) systems and more particularly to a novel EAS marker for use in an EAS system. 
   The problem of protecting articles of merchandise and the like against theft has been the subject of numerous technical approaches. One such type of approach has been to attach to the article an electronic tag or marker that is adapted to trigger an alarm or the like if the article of merchandise is moved beyond a predetermined location and the electronic marker has not been deactivated or removed from the article of merchandise. In the aforementioned type of approach, a transmitting apparatus and a receiving apparatus are typically situated on opposite sides of a passageway leading to an exit of the premises being protected, the transmitting apparatus and the receiving apparatus together defining an interrogation zone. The transmitting apparatus is typically used to transmit over the interrogation zone an interrogation signal that is recognizable by the EAS marker and that causes the EAS marker, if activated, to emit a response signal. The receiving apparatus is typically used to detect the presence of a response signal from an activated EAS marker located within the interrogation zone. The detection by the receiving apparatus of a response signal indicates that the EAS marker has not been removed or deactivated and that the article bearing the marker may not have been paid for or properly checked out. Typically, the detection of such a response signal by the receiving apparatus triggers an alarm. 
   Several different types of EAS markers have been disclosed in the literature and are in use. In one type of EAS marker, the functional portion of the marker consists of either an antenna and diode or an antenna and capacitors forming a resonant circuit. When placed in an electromagnetic interrogation zone created by the transmitting apparatus, the antenna-diode marker generates harmonics of the interrogation frequency in a receiving antenna in the receiving apparatus; the resonant circuit marker causes an increase in absorption of the transmitted signal so as to reduce the signal in the receiving apparatus. The detection of the harmonic or signal level change indicates the presence of the marker in the interrogation zone. With this type of system, the marker is not amenable to deactivation and, therefore, must be removed from the article of merchandise at the time of purchase so as not to trigger the alarm when the merchandise is removed from the store. 
   Examples of the aforementioned type of EAS marker are disclosed in U.S. Pat. No. 3,974,581, inventors Martens et al., which issued Aug. 17, 1976, and U.S. Pat. No. 4,774,504, inventor Hartings, which issued Sep. 27, 1988, both of which are incorporated herein by reference. 
   Another type of EAS marker includes a magnetostrictive element, also referred to in the art as “a resonator.” Typically, the resonator is in the form of a ribbon-shaped length of an amorphous magnetostrictive ferromagnetic material. Said type of EAS marker also typically includes a biasing magnetic element. The resonator is fabricated such that it is mechanically resonant at a predetermined frequency when the biasing element has been magnetized to a certain level and the resonator is brought into an interrogation zone consisting of an AC magnetic field of the predetermined frequency. In use, the biasing element is activated, i.e., magnetized, and the marker is brought into the interrogation zone, thereby causing the resonator to mechanically resonate at the predetermined frequency. This resonant signal radiated by the resonator is then detected by circuitry provided in the receiving apparatus. By demagnetizing the biasing element, the bias is removed from the resonator; accordingly, when subjected to the AC magnetic field, the resonator no longer resonates to produce a detectable magnetic field. The marker can thus be activated and deactivated by magnetizing and demagnetizing the biasing element. 
   Examples of the aforementioned magnetomechanical type of EAS marker are disclosed in the following U.S. patents, all of which are incorporated herein by reference: U.S. Pat. No. 4,510,489, inventors Anderson, III et al., which issued Apr. 9, 1985; U.S. Pat. No. 4,510,490, inventors Anderson, III et al., which issued Apr. 9, 1985; U.S. Pat. No. 4,622,543, inventors Anderson, III et al., which issued Nov. 11, 1986; U.S. Pat. No. 5,351,033, inventors Liu et al., which issued Sep. 27, 1994; U.S. Pat. No. 5,469,140, inventors Liu et al., which issued Nov. 21, 1995; U.S. Pat. No. 5,495,230, inventor Lian, which issued Feb. 27, 1996; U.S. Pat. No. 5,568,125, inventor Liu, which issued Oct. 22, 1996; U.S. Pat. No. 5,676,767, inventors Liu et al., which issued Oct. 14, 1997; U.S. Pat. No. 5,499,015, inventors Winkler et al., which issued Mar. 12, 1996; U.S. Pat. No. 5,565,849, inventors Ho et al., which issued Oct. 15, 1996; U.S. Pat. No. 5,494,550, inventor Benge, which issued Feb. 27, 1996; U.S. Pat. No. 5,357,240, inventors Sanford et al., which issued Oct. 18, 1994; and U.S. Pat. No. 6,067,016, inventors Deschenes et al., which issued May 23, 2000. 
   Another example of the aforementioned magnetomechanical EAS marker, which type is also one of the most widely used types of magnetomechanical EAS markers, comprises a plastic sheet material (e.g., styrene) which carries a heat seal coating. Said plastic sheet material is subjected to a thermoforming process to form a rectangular box-like housing with an open top bordered by a surrounding flange. A resonator is inserted into the housing through the open top, the resonator being curved slightly downwardly about its longitudinal axis. A clear, flexible, plastic sheet (e.g., polyethylene), often referred to as “lidstock,” is placed over the top of the housing and is heat-sealed or laminated to the border flange so as to close the housing, thereby encasing the resonator therewithin. Due to the aforementioned process of laminating the lidstock to the housing, a downward curve or “pillow” is typically formed in the midsection of the lidstock, said pillow delimiting upward movement of the resonator within the housing. A double-sided adhesively-coated carrier sheet is laid down over the lidstock and is secured to the border flange of the housing. A biasing magnetic element is secured to the underside of the carrier sheet. A peelable liner is applied to the top surface of the carrier sheet. When using the marker, the liner is peeled from the carrier and the exposed adhesive surface thereof is pressed against a desired article of merchandise, thereby securing the article and the marker together. Typically, the marker is manufactured as part of a batch using a multi-stationed, turntable-containing apparatus analogous to that described in U.S. Pat. No. 5,357,240. A commercial embodiment of the aforementioned marker is sold by Sensormatic Electronics Corporation (Deerfield Beach, Fla.) under the “UltraMax” trademark. 
   In U.S. Pat. No. 5,949,336, inventors Deschenes et al., which issued Sep. 7, 1999, and which is incorporated herein by reference, there is disclosed a fastener assembly for use in tagging an article of commerce and in detecting the unauthorized removal of the article from a store or other business establishment. The fastener assembly comprises a plastic fastener comprising an elongated filament having a first end and a second end, a transverse bar disposed at the first end of the elongated filament and a paddle disposed at the second end of the elongated filament. The paddle is shaped to include a recess. The fastener assembly also comprises an electronic article surveillance (EAS) security device which is disposed within the recess of the paddle. A cover is mounted over the recess so as to trap the security device within the paddle. A method of manufacturing the fastener assembly can be accomplished by continuously molding a length of fastener stock to form a plastic fastener having a recess formed therein, disposing a security device within the recess of the plastic fastener and mounting a cover over the recess so as to trap the security device within the fastener. 
   Other documents of interest include the following U.S. patents, all of which are incorporated herein by reference: U.S. Pat. No. 5,631,631, inventor Deschenes et al., which issued May 20, 1997; U.S. Pat. No. 5,717,382, inventor Cooper, which issued Feb. 10, 1998; U.S. Pat. No. 4,603,326, inventor Freed, which issued Jul. 29, 1986; U.S. Pat. No. 6,025,781, inventor Deschenes, which issued Feb. 15, 2000; and U.S. Pat. No. 6,064,306, inventors Deschenes et al., which issued May 16, 2000. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide a novel EAS marker for use in an EAS system. 
   It is another object of the present invention to provide an EAS marker as described above that is incorporated into a fastener attachable to articles of commerce. 
   According to a first aspect of the present invention, there is provided an EAS marker comprising (a) a plastic fastener, said plastic fastener comprising (i) an elongated flexible filament having a first end and a second end, (ii) a transverse bar disposed at said first end, (iii) a paddle disposed at said second end; (b) a cover secured to said paddle, said cover and said paddle jointly defining a compartment; (c) a resonator disposed within said compartment for emitting, when armed, a response signal in response to an interrogation signal transmitted by an EAS system; (d) a biasing element disposed within said compartment and positioned relative to said resonator so that, when said biasing element is magnetized, said resonator is armed; and (e) a separator disposed within said compartment between said resonator and said biasing element for physically separating said resonator and said biasing element. 
   According to a second aspect of the present invention, there is provided a clip of EAS markers, said clip comprising a pair of EAS markers as described above and a severable connector extending from the second end of the first transverse bar of the first EAS marker to the first end of the second transverse bar of the second EAS marker. 
   According to a third aspect of the present invention, there is provided an EAS marker comprising (a) a cable tie, said cable tie comprising (i) an elongated strap having a first end and a second end, said elongated strap being shaped to include a locking head at said first end, said locking head having a channel through which said second end of said elongated strap may be inserted and having a tang for lockably engaging said elongated strap, and (ii) a paddle coupled to said locking head; (b) a cover secured to said paddle, said cover and said paddle jointly defining a compartment; and (c) an EAS device disposed within said compartment. 
   According to a fourth aspect of the present invention, there is provided an EAS marker comprising (a) a self-lockable loop fastener, said self-lockable loop fastener comprising (i) an elongated strap having a first end and a second end, said second end being provided with an engageable member, (ii) a paddle disposed at said first end of said elongated strap, said paddle having a locking head, said second end of said elongated strap being insertable into, but not through, said locking head, said locking head having means for lockably engaging said engageable member on said elongated strap so as to form a locked loop of fixed size; (b) a cover secured to said paddle, said cover and said paddle jointly defining a compartment; and (c) an EAS device disposed within said compartment. 
   The present invention is also directed to a cable tie, said cable tie comprising (a) an elongated strap having a first end and a second end, said elongated strap being shaped to include a locking head at said first end, said locking head having a channel through which said second end of said elongated strap may be inserted and having a tang for lockably engaging said elongated strap, and (b) a paddle coupled to said locking head. 
   The present invention is further directed to a self-lockable loop fastener, said self-lockable loop fastener comprising (a) an elongated strap having a first end and a second end, said second end being provided with an engageable member, and (b) a locking head coupled to said first end of said elongated strap, said second end of said elongated strap being insertable into, but not through, said locking head, said locking head having means for lockably engaging said engageable member on said elongated strap so as to form a locked loop of fixed size. 
   Additional objects, features, aspects and advantages of the present invention will be set forth, in part, in the description which follows and, in part, will be obvious from the description or may be learned by practice of the invention. In the description, reference is made to the accompanying drawings which form a part thereof and in which is shown by way of illustration specific embodiments for practicing the invention. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are hereby incorporated into and constitute a part of this specification, illustrate preferred embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings wherein like reference numerals represent like parts: 
       FIG. 1  is a top perspective view of a first embodiment of an EAS marker constructed according to the teachings of the present invention; 
       FIG. 2  is an exploded perspective view of the EAS marker of  FIG. 1 ; 
       FIG. 3  is a section view of the EAS marker of  FIG. 1  taken along line  1 — 1 ; 
       FIG. 4  is a longitudinal section view of the plastic fastener shown in  FIG. 1 ; 
       FIG. 5  is a longitudinal section view of an alternate embodiment of the plastic fastener shown in  FIG. 4 ; 
       FIG. 6  is a top perspective view of a clip comprising a plurality of the EAS markers of  FIG. 1 ; 
       FIG. 7  is a partially exploded perspective view of the clip of  FIG. 6 ; 
       FIG. 8  is a top perspective view of a second embodiment of an EAS marker constructed according to the teachings of the present invention; 
       FIG. 9  is a fragmentary longitudinal section view of the EAS marker of  FIG. 8 ; 
       FIG. 10  is a top perspective view of a third embodiment of an EAS marker constructed according to the teachings of the present invention, said EAS marker being shown in a looped but not yet locked state; 
       FIG. 11  is a bottom perspective view of the EAS marker of  FIG. 10 , said EAS marker being shown in a locked loop state; 
       FIG. 12  is an exploded top perspective view of the EAS marker of  FIG. 10 , said EAS marker being shown in a locked loop state; 
       FIG. 13  is an exploded bottom perspective view of the EAS marker of  FIG. 10 , said EAS marker being shown in a locked loop state; 
       FIG. 14  is an enlarged fragmentary perspective view of the EAS marker of  FIG. 10 , showing details of the second end of the elongated strap of the self-lockable loop fastener; 
       FIG. 15  is an enlarged fragmentary longitudinal section view of the self-lockable loop fastener shown in  FIG. 10 , illustrating details of the paddle thereof; 
       FIG. 16  is a top perspective view of a fourth embodiment of an EAS marker constructed according to the teachings of the present invention, said EAS marker being shown in a locked looped state; 
       FIG. 17  is a bottom perspective view of the EAS marker of  FIG. 16 , said EAS marker being shown in a locked loop state; 
       FIG. 18  is an exploded bottom perspective view of the EAS marker of  FIG. 16 , said EAS marker being shown in a locked loop state; and 
       FIG. 19  is an exploded top perspective view of the EAS marker of  FIG. 16 , said EAS marker being shown in a locked loop state. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   Referring now to  FIGS. 1 through 3 , there are shown various views of a first embodiment of an EAS marker constructed according to the teachings of the present invention, said EAS marker being represented generally by reference numeral  11 . 
   Marker  11  comprises a plastic fastener  13  (plastic fastener  13  being shown separately in  FIG. 4 ). Plastic fastener  13 , which may be made, for example, by injection molding, comprises an elongated flexible filament  15  having a first end and a second end. A transverse bar  17  is disposed at the first end of filament  15 , and a paddle  19  is disposed at the second end of filament  15 . Paddle  19  is a trough-shaped member shaped to include a rectangular recess  21  having an open top and being bounded by a bottom wall  23  and four side walls  25 - 1  through  25 - 4 . 
   Marker  11  also comprises a biasing element  31 , a separator  33 , and a resonator  35 , all of which are disposed within recess  21 , with biasing element  31  being positioned directly on top of bottom wall  23 , separator  33  being positioned directly on top of biasing element  31  and resonator  35  being positioned directly on top of separator  33 . Biasing element  31  and resonator  35  are preferably conventional in structure and composition and may be, for example, similar to biasing element  51  and resonator  41 , respectively, of U.S. Pat. No. 6,067,016. Separator  33  is similar in structure and composition to separator  83  of U.S. Pat. No. 6,067,016. 
   Marker  11  further comprises a cover  41 , cover  41  being secured to paddle  19  in such a way as to securely encapsulate within recess  21  the combination of biasing element  31 , separator  33  and resonator  35 . Cover  41 , which is preferably made of a molded material similar in composition to plastic fastener  13 , is preferably secured to paddle  19  by ultrasonic welding. Alternatively, cover  41  may be secured to paddle  19  by any other suitable method, such as by a suitable adhesive, by a frictional or interlocking fit or the like. Cover  41  may be flat on its inside surface or, as in the present embodiment, may be a trough-shaped member shaped to include a shallow recess  42  (as seen best in  FIG. 3 ) having an open bottom, recess  42  being similar in shape to recess  21 . Cover  41  and paddle  19  are preferably made of a sufficiently rigid material to protect the contents of recess  21  since biasing element  31 , separator  33  and resonator  35  are encapsulated only by cover  41  and paddle  19 . 
   Although, in the present embodiment, cover  41  and paddle  19  are shown as two separate pieces which are secured in the manner described above, it can readily be appreciated that cover  41  and paddle  19  could be formed as a unitary structure, with end  41 - 1  of cover  41  being hingedly interconnected to the end of paddle  19  distal to transverse bar  17  (as illustrated by fastener  47  shown in  FIG. 5  wherein end  41 - 1  of cover  41  is hingedly interconnected to end  19 - 1  of paddle  19  by a hinge  49 ). In this manner, cover  41  may be pivoted away from paddle  19  while biasing element  31 , separator  33  and resonator  35  are loaded into recess  21 ; thereafter, cover  41  may be pivoted into contact with paddle  19  and secured thereto in the manner described above. 
   It should also be understood that fastener  13  could be modified so that cover  41 , and not paddle  19 , is disposed at the second end of filament  15 , with paddle  19  being a separate piece from fastener  13  that is later secured to cover  41  in the manner described above or with paddle  19  and cover  41  being hingedly interconnected, as in the case of fastener  47 . 
   Marker  11  is intended to be attached to articles of commerce in the same manner as a typical plastic fastener and, thereafter, is intended to be used in the same fashion as a conventional magnetomechanical EAS marker. 
   Referring now to  FIGS. 6 and 7 , there are shown various views of a clip comprising a plurality of EAS markers  11 , said clip being constructed according to the teachings of the present invention and being represented generally by reference numeral  51 . 
   Clip  51  comprises a plurality of EAS markers  11  arranged in an end-to-end fashion with respect to transverse bars  17 . Clip  51  also comprises severable connectors  53  for interconnecting adjacent transverse bars  17 . Adjacent paddles  19  are not interconnected. The plastic fasteners  13  of clip  51  may be made by index molding, with gating being through paddles  19  via an interconnected runner outboard of the paddle (not shown). Stretching of the filaments  15  could be done in-line, one cavity length at a time (a cavity defining, for example, four to eight interconnected fasteners). Cover  41  could also be made by index molding. Assembly of clip  51  could be automated using lengths of index-molded fasteners  13  and covers  41 , together with strips of the biasing element  31 , separator  33  and resonator  35 . 
   It should be understood that, instead of making interconnected fasteners  13  of clip  51  by index molding, as mentioned above, one could form an interconnected plurality of similar fasteners by a continuous rotary extrusion technique of the type described in U.S. Pat. No. 5,949,336. (An example of the resulting fastener is shown in FIGS. 3 and 4 of U.S. Pat. No. 5,949,336.) 
   Referring now to  FIGS. 8 and 9 , there are shown various views of a second embodiment of an EAS marker constructed according to the teachings of the present invention, said second embodiment of an EAS marker being represented generally by reference numeral  81 . 
   Marker  81  comprises a cable tie, said cable tie comprising an elongated strap  83  having a first end  84 - 1  and a second end or tail  84 - 2 . A locking head  85  is disposed at first end  84 - 1  of strap  83 , locking head  85  having a channel  87  through which tail  84 - 2  may be inserted. Channel  87  also has a tang  89  for lockably engaging a selected tooth  91  formed on elongated strap  83  to form a loop of fixed size in the conventional manner. Tang  89  and teeth  91  are conventional in structure, and the number of teeth  91  shown formed on strap  83  is merely illustrative. (Instead, of teeth  91 , strap  83  may have a conventional ladder-type shape adapted to engage tang  89 .) 
   A paddle  93  is connected to locking head  85  by a spacer  86 , paddle  93  being a trough-shaped member having a recess  95 . Paddle  93  and recess  95  are identical in size and shape to paddle  19  and recess  21 , respectively, of marker  11 . The longitudinal axis of paddle  93  is collinear with the longitudinal axis of strap  83 . 
   Preferably, paddle  93 , spacer  86 , locking head  85  and strap  83  are formed as a unitary structure made of molded plastic. 
   Marker  81  further comprises a biasing element  97 , a separator  99 , and a resonator  101 , biasing element  97 , separator  99  and resonator  101  being identical to biasing element  31 , separator  33  and resonator  35 , respectively, of marker  11  and being disposed within recess  95  in an analogous fashion to that of marker  11 . 
   Marker  81  further comprises a cover  103 , cover  103  being identical to cover  41  of marker  11  and being secured to paddle  93  in the same manner in which cover  41  is secured to paddle  19  so as to securely encapsulate within recess  95  the combination of biasing element  97 , separator  99  and resonator  101 . Biasing element  97 , separator  99  and resonator  101  are encapsulated only by cover  103  and paddle  93 . 
   Although, in the present embodiment, cover  103  and paddle  93  are shown as two separate pieces which are secured in the manner described above, it can readily be appreciated that cover  103  and paddle  93  could be formed as a unitary structure, with end  103 - 1  of cover  103  being hingedly interconnected to the end of paddle  93  distal to tail  84 - 2 . In this manner, cover  103  may be pivoted away from paddle  93  while biasing element  97 , separator  99  and resonator  101  are loaded into recess  95 ; thereafter, cover  103  may be pivoted into contact with paddle  93  and secured thereto in the manner described above. It should also be understood that cover  103 , instead of paddle  93 , may be coupled to locking head  85  by spacer  86 . 
   Marker  81  is intended to be attached to articles of commerce in the same manner as a typical cable tie and, thereafter, is intended to be used in the same fashion as a conventional magnetomechanical EAS marker. 
   In another embodiment (not shown), spacer  86  is eliminated and locking head  85  is incorporated into paddle  93 . 
   Referring now to  FIGS. 10 through 14 , there are shown various views of a third embodiment of an EAS marker constructed according to the teachings of the present invention, said third embodiment of an EAS marker being represented generally by reference numeral  101 . 
   Marker  101  comprises a self-lockable loop fastener  103  (self-lockable loop fastener  103  being shown separately in  FIG. 15 ). Fastener  103 , which is preferably a unitary structure made of molded plastic, comprises an elongated flexible strap  105 , strap  105  having a first end  107  and a second end  109 . As seen best in  FIG. 14 , the top surface of strap  105 , proximate to second end  109 , is provided with a projection  121  and the bottom surface of strap  105 , proximate to second end  109 , is provided with a plurality of teeth  123 . Teeth  123  are similar in size and shape to the teeth commonly found at the tail end of a strap of a conventional cable tie. The functions of projection  121  and teeth  123  will become apparent below. 
   Referring now to  FIGS. 10 through 15 , fastener  103  also comprises a paddle  125 , paddle  125  being attached to first end  107  of strap  105 . Paddle  125  is a generally rectangularly-shaped member having a top wall  127 , a front wall  129 , a rear wall  131 , a pair of side walls  133 - 1  and  133 - 2  and an open bottom  135 . A locking head  137  is integrally formed on paddle  125  proximate to rear wall  131 , locking head  137  being closed at its rear end but having a slotted opening  139  extending longitudinally (relative to paddle  125  and strap  105 ) rearwardly for a distance from its front end. Locking head  137  and opening  139  are appropriately sized and shaped to permit second end  109  of strap  105  to be inserted into locking head  137  through opening  139 . (Because locking head  137  is open at only one end, strap  105  cannot be inserted entirely through locking head  137 .) A tang  141  is pivotally mounted within locking head  137  and is engageable with teeth  123  on strap  105  in such a way as to prevent withdrawal of strap  105  from locking head  137  once teeth  123  have been advanced past tang  141 . Projection  121 , which is appropriately sized and shaped to be engageable with locking head  137 , serves to ensure that teeth  123  are brought into proximity with tang  141 . In view of the above, as can readily be appreciated, once teeth  123  have been advanced past tang  141 , strap  105  cannot be withdrawn from locking head  137 ; moreover, due to locking head  137  being open at only one end, since strap  105  cannot be inserted entirely through locking head  137 , advancement of teeth  123  past tang  141  results in a locked loop. 
   As seen best in  FIGS. 10 ,  12  and  15 , opening  139  is widest at its entrance (the front end of locking head  137 ) to facilitate insertion of strap  105  thereinto. 
   Referring now to  FIGS. 13 and 15 , paddle  125  can be seen to also be shaped to include a downwardly-facing recess or compartment  143  situated in front of the majority of locking head  137 . The function of compartment  143  will become apparent from the discussion below. 
   Referring now to  FIGS. 12 and 13 , marker  101  also comprises a biasing element  151 , a separator  153 , and a resonator  155 , all of which are disposed within compartment  143 , with biasing element  151  being positioned directly in contact with the bottom surface of top wall  127 , separator  153  being positioned directly on top of biasing element  151  and resonator  155  being positioned directly on top of separator  153 . Biasing element  151  and resonator  155  are preferably conventional in structure and composition and may be identical to biasing element  31  and resonator  35  of marker  11 . Separator  153  is identical in structure and composition to separator  33  of marker  11 . 
   Marker  101  further comprises a cover  157 , cover  157  being made of a material similar in composition to that used to make fastener  103 . Cover  157  is secured to paddle  125  in such a way as to securely encapsulate within compartment  143  the combination of biasing element  151 , separator  153  and resonator  155  and to prevent unauthorized access to and tampering with locking head  137  and tang  141  from below. In the present embodiment, cover  157  is secured to paddle  125  by ultrasonic welding, but it can readily be appreciated that cover  157  may alternatively be secured to paddle  125  by a suitable adhesive, by a frictional or interlocking fit or by any other suitable method. Cover  157  and paddle  125  are preferably made of a sufficiently rigid material to protect the contents of compartment  143  since biasing element  151 , separator  153  and resonator  155  are encapsulated only by cover  157  and paddle  125 . Cover  157  is preferably sufficiently opaque to conceal the contents of compartment  143  for security purposes. The bottom surface of cover  157  may be imprinted with labeling information for commercial purposes or a label may be affixed to the bottom surface of cover  157 . 
   Although, in the present embodiment, cover  157  and paddle  125  are shown as two separate pieces which are secured in the manner described above, it can readily be appreciated that cover  157  and paddle  125  could be formed as a unitary structure, with end  157 - 1  of cover  157  being hingedly interconnected to wall  129  of paddle  125 . In this manner, cover  157  may be pivoted away from paddle  125  while biasing element  151 , separator  153  and resonator  155  are loaded into compartment  143 ; thereafter, cover  157  may be pivoted into contact with paddle  125  and secured thereto in the manner described above. 
   Marker  101  is intended to be attached to articles of commerce in the same manner as a typical self-lockable loop fastener and, thereafter, is intended to be used in the same fashion as a conventional magnetomechanical EAS marker. 
   Referring now to  FIGS. 16 through 19 , there are shown various views of a fourth embodiment of an EAS marker constructed according to the teachings of the present invention, said EAS marker being represented generally by reference numeral  201 . 
   Marker  201  is similar in virtually all respects to marker  101 , the principal difference between the two markers being that marker  201  includes a paddle  203  whose locking head  205  and tang  207  are oriented 180 degrees relative to locking head  137  and tang  141 , respectively, of marker  101 . In other words, the slotted opening  206  of head  205  extends longitudinally (relative to paddle  203  and strap  105 ) a short distance from the open rear end of head  205  towards the closed front end of head  205 . 
   The embodiments of the present invention recited herein are intended to be merely exemplary and those skilled in the art will be able to make numerous variations and modifications to it without departing from the spirit of the present invention. All such variations and modifications are intended to be within the scope of the present invention as defined by the claims appended hereto.