shimano Original authentic, quality assurance 7/8 speed, professional rear derailleur Suitable for mountain bikes and folding bikes Super cost-effective, accurate and reliable direction change Condition: Brand New Model: RD-M310 Black Compatible with: 7/8 speeds Largest Cog: 34T Chain Wrap Capacity: 43T Weight: approx. 315g Package includes: & 1pcs M310 7 /8 Speed RD & 1pcs M310 7s Shifter & 1pcs M310 8s Shifter sprocket tooth speed difference 20T convection range total value 43T smaller tooth speed compatible 11 / 14T large tooth speed compatible 28 / 34T