A clamshell stapling end effector includes first and second jaws and definesan endeffector axis. The first jaw has proximal, central, and distal portions. Thecentralportion includes a first tissue contacting surface and defines a cavity. Thesecond jawincludes a second tissue contacting surface and is rotatably secured to thefirst jawabout a rotation axis. The rotation axis is parallel to the end effector axis.The secondjaw has a folded position such that the second jaw is positioned within thecavity ofthe first jaw with the first and second tissue contacting surfaces parallel toone anotherand facing in the same direction and a clamped position such that the firstand secondtissue contacting surfaces oppose one another.