A surgical fastening apparatus, comprising: a handle assembly； a central body portion extending from the handle assembly； and a distal head portion including a shell assembly and an anvil assembly, the anvil assembly including: an anvil head assembly including an anvil head defining an interior recess supporting an activator plate, a deformable member positioned distally of the activator plate, and a securing member positioned proximally of the activator plate； and an anvil center rod assembly defining a longitudinal axis and being pivotably connected to the anvil head assembly about a pivot axis and including a plunger in mechanical communication with the anvil head, the plunger configured to contact the anvil head assembly upon an actuation of the surgical fastening apparatus； wherein, upon the actuation of the surgical fastening apparatus, the deformable member is configured to deform such that the activator plate is advanced distally into the interior recess to facilitate the anvil head pivoting about the pivot axis.
