ZP-A80-T2 CRANK 曲柄 A80-170mm (Alloy Forged 6061-T6) CHAIN RING 链轮 32T*50T(steel) SPIDER 爪 BCD 104/64mm CHAINLINE 链线 43.5mm COMPATIBIL ITY 变速兼容 2*9S/10S B.B.T 中轴 Chrome molybdenum steel