A fastener cartridge, comprising: a body extending along a longitudinal axis; fasteners removably positioned in the body; and drivers movably supporting the fasteners, wherein the drivers comprise a first driver comprising: a first support column defining a first width (Wa) and comprising a first proximal end and a first distal end; a second support column laterally outboard from the first support column and defining a second width (Wb) and comprising a second proximal end and a second distal end; and a third support column laterally outboard from the second support column and defining a third width (Wc) and comprising a third proximal end and a third distal end, wherein cavities are defined in the body, and wherein the cavities comprise: a first cavity comprising first lateral guide surfaces configured to slidably engage the first support column; a second cavity comprising second lateral guide surfaces configured to slidably engage the second support column, a third cavity comprising third lateral guide surfaces configured to slidably engage the third support column; and wherein the first support column comprises first opposing sidewalls extending longitudinally between the first proximal end and the first distal end configured to slidably engage the first lateral guide surfaces, wherein the first width is the maximum width defined between the first sidewalls, wherein the second support column comprises second opposing sidewalls extending longitudinally between the second proximal end and the second distal end configured to slidably engage the second lateral guide surfaces, wherein the second width is the maximum width defined between the second sidewalls, wherein the third support column comprises third opposing sidewalls extending longitudinally between the third proximal end and the third distal end configured to slidably engage the third lateral guide surfaces, and wherein the third width is the maximum width defined between the third sidewalls; characterized in that the first width, the second width, and the third width are different widths. a body extending along a longitudinal axis; fasteners removably positioned in the body; and drivers movably supporting the fasteners, wherein the drivers comprise a first driver comprising: a first support column defining a first width (Wa) and comprising a first proximal end and a first distal end; a second support column laterally outboard from the first support column and defining a second width (Wb) and comprising a second proximal end and a second distal end; and a third support column laterally outboard from the second support column and defining a third width (Wc) and comprising a third proximal end and a third distal end, a first support column defining a first width (Wa) and comprising a first proximal end and a first distal end; a second support column laterally outboard from the first support column and defining a second width (Wb) and comprising a second proximal end and a second distal end; and a third support column laterally outboard from the second support column and defining a third width (Wc) and comprising a third proximal end and a third distal end, wherein cavities are defined in the body, and wherein the cavities comprise: a first cavity comprising first lateral guide surfaces configured to slidably engage the first support column; a second cavity comprising second lateral guide surfaces configured to slidably engage the second support column, a third cavity comprising third lateral guide surfaces configured to slidably engage the third support column; and a first cavity comprising first lateral guide surfaces configured to slidably engage the first support column; a second cavity comprising second lateral guide surfaces configured to slidably engage the second support column, a third cavity comprising third lateral guide surfaces configured to slidably engage the third support column; and wherein the first support column comprises first opposing sidewalls extending longitudinally between the first proximal end and the first distal end configured to slidably engage the first lateral guide surfaces, wherein the first width is the maximum width defined between the first sidewalls, wherein the second support column comprises second opposing sidewalls extending longitudinally between the second proximal end and the second distal end configured to slidably engage the second lateral guide surfaces, wherein the second width is the maximum width defined between the second sidewalls, wherein the third support column comprises third opposing sidewalls extending longitudinally between the third proximal end and the third distal end configured to slidably engage the third lateral guide surfaces, and wherein the third width is the maximum width defined between the third sidewalls; characterized in that the first width, the second width, and the third width are different widths.