Ofna two speed transmission is an unassembled two speed transmission. This kit includes two speed transmission, 1st gear holder, center shaft, aluminum nut, clutch cam set, 4mm set screw, 5x10mm bearing, 18mm E-ring, clutchbell base, olastic 45 tooth spur gear (2nd gear), plastic 49 tooth spur gear (1st gear), metal 18 tooth pinion (2nd gear), metal 14 tooth pinion (1st gear), dust cover, and instuctions.