A surgical instrument (10, 500) comprising: a handle assembly; an elongate member extending from the handle assembly; a tool assembly having a first jaw and a second jaw at a distal portion of the elongate member; a drive assembly operatively associated with the handle assembly and configured to translate through the tool assembly upon actuation of the handle assembly, the drive assembly including: a drive beam (266, 750, 802); an end member (184, 284, 384) projecting distally from the drive beam (266, 802) and having an upper portion and a lower portion; at least one of the first jaw and the second jaw is movable in response to translation of the drive assembly, wherein the second, movable jaw is one of an anvil (20, 880) or a staple cartridge and has a longitudinal slot presenting a camming surface, wherein the upper portion of the end member (184, 284, 384) extends distally in relation to the lower portion of the end member (184, 284, 384), forming a cantilevered portion (184, 191), the cantilevered portion supports one or more cam members; the lower portion provides a sled pushing member proximally of the cam members whereby, on actuation of the drive assembly by the handle assembly the cam members translate distally to approximate the second movable jaw by engagement with the camming surface and the sled pushing member engages and distally moves an activation sled which fires a series of staples from the staple cartridge towards the opposing anvil (20, 880) the cam members perpendicularly overlie the activation sled and characterized in that a cap (186, 291, 386) is attached to the upper portion of the end member (184, 284, 384), the cap (186, 291) having a different thickness than the end member (184, 284, 384) to reinforce the cantilevered portion in the direction transverse to a longitudinal axis defined by the drive beam during translation through tool assembly such that it carries more load when pulling the first jaw into clamping position on thicker tissue. a handle assembly; an elongate member extending from the handle assembly; a tool assembly having a first jaw and a second jaw at a distal portion of the elongate member; a drive assembly operatively associated with the handle assembly and configured to translate through the tool assembly upon actuation of the handle assembly, the drive assembly including: a drive beam (266, 750, 802); an end member (184, 284, 384) projecting distally from the drive beam (266, 802) and having an upper portion and a lower portion; at least one of the first jaw and the second jaw is movable in response to translation of the drive assembly, wherein the second, movable jaw is one of an anvil (20, 880) or a staple cartridge and has a longitudinal slot presenting a camming surface, wherein the upper portion of the end member (184, 284, 384) extends distally in relation to the lower portion of the end member (184, 284, 384), forming a cantilevered portion (184, 191), the cantilevered portion supports one or more cam members; the lower portion provides a sled pushing member proximally of the cam members whereby, on actuation of the drive assembly by the handle assembly the cam members translate distally to approximate the second movable jaw by engagement with the camming surface and the sled pushing member engages and distally moves an activation sled which fires a series of staples from the staple cartridge towards the opposing anvil (20, 880) a drive beam (266, 750, 802); an end member (184, 284, 384) projecting distally from the drive beam (266, 802) and having an upper portion and a lower portion; at least one of the first jaw and the second jaw is movable in response to translation of the drive assembly, wherein the second, movable jaw is one of an anvil (20, 880) or a staple cartridge and has a longitudinal slot presenting a camming surface, wherein the upper portion of the end member (184, 284, 384) extends distally in relation to the lower portion of the end member (184, 284, 384), forming a cantilevered portion (184, 191), the cantilevered portion supports one or more cam members; the lower portion provides a sled pushing member proximally of the cam members whereby, on actuation of the drive assembly by the handle assembly the cam members translate distally to approximate the second movable jaw by engagement with the camming surface and the sled pushing member engages and distally moves an activation sled which fires a series of staples from the staple cartridge towards the opposing anvil (20, 880) the cam members perpendicularly overlie the activation sled and characterized in that a cap (186, 291, 386) is attached to the upper portion of the end member (184, 284, 384), the cap (186, 291) having a different thickness than the end member (184, 284, 384) to reinforce the cantilevered portion in the direction transverse to a longitudinal axis defined by the drive beam during translation through tool assembly such that it carries more load when pulling the first jaw into clamping position on thicker tissue.