A surgical stapling device including a handle assembly, a body portionextending distallyfrom the handle assembly, a head portion including an anvil retainer and ashell assembly, theanvil retainer being movable in relation to the shell assembly betweenunapproximated andapproximated positions, a tube surrounding a portion of the anvil retainer,wherein the anvilretainer includes a distal annular protrusion for releasably engaging an anvilassembly andwherein the anvil assembly includes a center rod.
