1、MULTI SHIFT GROUP SET: Including 9 speed freewheel, hollow integrated crank, shift lever, rear derailleur, chain, tail hook and other accessories. 2、STEEL PLATE: The freewheel adopts high strength steel plate and has been quenched, tempered and hardened, very sturdy. 3、RUST PREVENTION: The surface is multiple layer electroplated, which is rust prevention, with drop gear design, ensuring smoother speed change. 4、ALUMINUM ALLOY CRANK: The crank is made of aluminum alloy, sturdy and light, has stylish look, strong axial strength, and wide compatibility. 5、DIY YOUR BIKE: This set is great for family or friends who like cycling, allowing them to DIY their own bikes and upgrade performance. Item Type: 9 Speed Groupset Material: Aluminum Alloy Teeth Number: 11-13-16-20-24-28-32-36-40T 1 x 9 Speed Freewheel 3 x Freewheel Accessories 1 x Tail Hook 1 x Tail Hook Accessory 1 x Front Derailleur 1 x Rear Derailleur 1 x Chain 2 x Chain Buckle 1 x Chain Box 1 x Left Crank 1 x Right Crank 1 x Bottom Bracket 10 x Crank Accessories 1 x Crankset