MTB Mountain Road Bike Steel Bicycle Crank Arm 130mm BCD Crankset + Bottom Bracket +Chainring Product Description: Model: (single disc) mountain bike crank set Crank length: 152/165/170mm Crank: 130BCD Surface treatment: Anodizing Gear disc specification: 39-50T (gear disc diameter) Compatible: single disk, double disk and three disk Axis material: chrome molybdenum steel Weight:764.2g Suitable for: road bike ,mountain bike Package Contents:1 Set as your choice