Features:1. Made of premium aluminium alloy, which is lightweight, adding no heaviness to bike.2. High strength and deformation resistance, durable for long time use.3. Standard precision machining, which ensures ultimate chain retention, increases service life, and reduces friction and noise.4. 170mm crank arm length without any overlap of crank arm and chain ring bolt.5. An ideal replacement for bike repair, compatible with many bike models.6. Suitable for Shimano, Prowheel, Sunrace, Truvativ, Sram, etc.Specification:Material: Aluminium AlloyColor Options: Black, Red, Blue, GoldBCD: 104 mm / 4.1inCrank Arm Length: 170 mm / 6.7inBottom Bracket Length: 98mm / 3.9inNot Compatible: Triple DiskFit for: Single Speed OnlyWeight: Approx. 1065g / 37.6ozPackage list: 1 * Crankset1 * Pair of Crank Arms1 * Bottom Bracket Note:68mm bottom bracket, two washers on the right, one washer on both sides.73mm bottom bracket, one washer on the right, no washer on the left, The reducer ring in the middle shaft should be removed when matching the tooth plate, otherwise the hollow shaft of the tooth plate cannot pass through.