IS: 51mm International Standard

Who's this item for: It's a useful tool for anyone that needs to check the condition of their chain and cassette

laser cut steel the Unior Chain Wear Indicator has been built for the long haul

Cons: These levers aren't directly compatible with some other brands of posts as the cable clamp bolt is at the lever - not on the post

Shimano GRX RD-RX822 Shadow+ 12 Speed Rear Derailleur - Rear Derailleur - 12 Speed - Black - Mid Cage - 1x12 - 45T Max PLP|Model Year IS: 51mm International StandardWith its integrated chain stabilizer and medium cage, the SHIMANO GRX rear derailleur delivers quieter shifting, better ground clearance and more secure chain management in rough terrain. The RD RX822 SGS is compatible with 10 51T, 12 speed SHIMANO MTB cassettes, and the chain tensioner has an ON OFF switch for easy wheel removal.