A fastener cartridge assembly. The fastener cartridge assembly can comprise a cartridge body, a tissue thickness compensator releasably secured relative to the cartridge body, and a fastener removably positioned in a staple cavity of the cartridge body. The tissue thickness compensator can comprise a first clearance aperture extending along a first predefined trajectory and a second clearance aperture extending along a second predefined trajectory. The fastener can comprise a first leg aligned with the first clearance aperture and moveable along the first predefined trajectory, a second leg aligned with the second clearance aperture and moveable along the second predefined trajectory. The first and second predefined trajectories can be parallel.
