microSHIFT R10 rear derailleurs feature forged and CNC machined construction that pairs durability with a quality finish. This lightweight and lightweight rear derailleur is robust and designed to get any 10-speed Shimano Road compatible bike back on the road.Medium cage has 39t capacity30-34t Max cogForged and CNC machined aluminum construction is lightweight and ruggedCage is crafted with steel for enhanced chain-rub durabilityFor use with Shimano 10-speed road systemsNot compatible with Shimano Tiagra 4700 road systemItem SpecificationsCage LengthMediumChain Wrap Capacity (teeth)39ColorBlackDrivetrain Speeds10Largest Cog34Rear Der/Shifter CompatibilityShimano RoadRear Derailleur Mount Type10x1 Standard microSHIFT R10 10-Speed Rear Derailleur Rear Derailleur EAN: 4710495436593