A staple gap adjustment member for use in a surgical stapling apparatus having a pair of jaw structures (110, 120) operably coupled with one another and defining a staple gap therebetween, the gap adjustment member comprising: one or more bearing portions (210, 230) sharing a common rotational axis; wherein the gap adjustment member is an eccentric cam comprising: the one or more bearing portions (210, 230); and one or more cam surface portions having a periphery with at least two different points along the periphery, with each point along the periphery having a different radius from the rotational axis, wherein: the one or more cam surface portions has a central axis parallel to and spaced a distance X from the rotational axis of the one or more bearing portions, wherein the one or more bearing portions (210, 230) include a forward portion and a rearward portion and the one or more cam surface portions include a body portion, wherein the central axis of the body portion is spaced the distance X from the common rotational axis of the forward and rearward portions (210, 230); wherein the forward portion and the rearward portion are configured and adapted to be received in a pair of receiving recesses of hinge plates of the surgical stapling apparatus; wherein an anvil receiving structure of the surgical stapling apparatus is configured and adapted to be disposed between the pair of hinge plates and to sit on and ride atop the body portion of the eccentric cam; and wherein as the eccentric cam is rotated about the common axis of the forward and rearward portions (210, 230), the body portion presses against the anvil receiving structure, rotating a rearward portion of the anvil receiving structure about a pivot pin, thereby altering the spatial distance between the anvil receiving structure and a cartridge receiving structure by a maximum distance of 2X. one or more bearing portions (210, 230) sharing a common rotational axis; wherein the gap adjustment member is an eccentric cam comprising: the one or more bearing portions (210, 230); and one or more cam surface portions having a periphery with at least two different points along the periphery, with each point along the periphery having a different radius from the rotational axis, wherein: the one or more cam surface portions has a central axis parallel to and spaced a distance X from the rotational axis of the one or more bearing portions, wherein the one or more bearing portions (210, 230) include a forward portion and a rearward portion and the one or more cam surface portions include a body portion, wherein the central axis of the body portion is spaced the distance X from the common rotational axis of the forward and rearward portions (210, 230); wherein the forward portion and the rearward portion are configured and adapted to be received in a pair of receiving recesses of hinge plates of the surgical stapling apparatus; wherein an anvil receiving structure of the surgical stapling apparatus is configured and adapted to be disposed between the pair of hinge plates and to sit on and ride atop the body portion of the eccentric cam; and wherein as the eccentric cam is rotated about the common axis of the forward and rearward portions (210, 230), the body portion presses against the anvil receiving structure, rotating a rearward portion of the anvil receiving structure about a pivot pin, thereby altering the spatial distance between the anvil receiving structure and a cartridge receiving structure by a maximum distance of 2X. the one or more cam surface portions has a central axis parallel to and spaced a distance X from the rotational axis of the one or more bearing portions, wherein the one or more bearing portions (210, 230) include a forward portion and a rearward portion and the one or more cam surface portions include a body portion, wherein the central axis of the body portion is spaced the distance X from the common rotational axis of the forward and rearward portions (210, 230); wherein the forward portion and the rearward portion are configured and adapted to be received in a pair of receiving recesses of hinge plates of the surgical stapling apparatus; wherein an anvil receiving structure of the surgical stapling apparatus is configured and adapted to be disposed between the pair of hinge plates and to sit on and ride atop the body portion of the eccentric cam; and wherein as the eccentric cam is rotated about the common axis of the forward and rearward portions (210, 230), the body portion presses against the anvil receiving structure, rotating a rearward portion of the anvil receiving structure about a pivot pin, thereby altering the spatial distance between the anvil receiving structure and a cartridge receiving structure by a maximum distance of 2X.