A surgical stapling device comprising an end effector. According to various embodiments, the end effector comprises an anvil having a staple forming surface and a plurality of staples facing the staple forming surface of the anvil. The end effector also comprises a plurality of staple drivers moveable supported within the staple cartridge. Each staple driver is in contact with one of the plurality of staples such that when the staple drivers are actuated, the plurality of staples are formed against the staple forming surface of the anvil. A first quantity of the staple drivers have a first height and a second quantity of the staple drivers have a second height, wherein the first height is less than the second height such that the staples driven by the first quantity of staple drivers have a longer formed length than the staples driven by the second quantity of staple drivers.