This product is suitable for retrofit folding bike, bike, electric bike. lightweight, high axial strength and compatibility. Standard precision machining, chain retention, increases service life, and reduces friction. A good replacement for bike repair and upgradation, compatible with many bike models. 170mm crank arm length without any overlap of crank arm and chain ring bolt. Specifications 48TBED double cover x 170MM handle square hole, with 9 16inch pedal axle, chain cover, Introduction Compatible with 6 7 speed post change, installation recommendation suitable for lithium battery bicycle type lithium battery bicycle etc. Colour black Material aluminum alloy Package Contents 1 x Crank set Only the above package content, other products are not included. Note Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1 3cm.