MATERIAL QUALITY:Made of premium aluminium alloy, lightweight, high strength and deformation resistance, durable for long time use.CRANK ARE LENGTH: 170mm crank arm length without any overlap of crank arm and chain ring bolt.PERFECT CUTTING: Standard quality cutting of hole, which ensures to bike, easy to install.Suitable for road bike, mountain bike, folding bike, fixed gear bicycle, etc.Note: 10 grooves need to correspond to the bicycle bottom bracket should have 10 grooves.Colour:blackMaterial:Aluminum alloyPackage Contents:1 x bicycle crank armOnly 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.