A surgical stapling device is provided having a shell assembly including an outer housing portion having areas of varying wall thicknesses. Individual staple pockets in a row of staple pockets are positioned in areas of thinner wall thicknesses. Areas of increased wall thicknesses form longitudinally extending strengthening ribs along an inner surface of the outer housing portion. The longitudinally extending strengthening ribs may be solid, indented in the wall of the outer housing portion and or bisected by a slot extending through the outer housing portion.