YAD Aluminum Alloy 7/8/9 Speed Crankset 24T/34T/42T Triple Crankset 170mm Crank with Chain Cover (blue with black teeth) Material: aluminum alloy crank + high carbon steel tooth wheel Crank Length: 170mm/6.7inch; Chain Cover: Plastic Chainwheel Teeth: 24T-34T-42T; Weight: About 0.8kg Chainwheel Speed: 7-speed, 8-speed, 9-speed Fit axial length: 118-122.5mm, Compatible: Square hole 115mm