In various embodiments of the present invention, a piece of buttress material can be configured to match a curved profile of the anvil and/or staple cartridge of a surgical stapler. In at least one embodiment, the piece of buttress material can include first and second edges extending between first and second ends. In these embodiments, the first edge can be defined by a first radius of curvature and the second edge can be defined by a second radius of curvature wherein the second radius of curvature is larger than the first radius of curvature. In at least one embodiment, the anvil and/or staple cartridge can include a surface configured for receiving a piece of buttress material thereon and a lip which at least partially extends along the periphery thereof wherein the lip can be configured to reduce relative movement between the piece of buttress material and the surface.
