Pivot Patte Derailleur Arrière UDH 12mmThe Universal Derailleur Hanger consolidates thousands of hanger options across the industry. It protects your derailleur against chain jams by pivoting back and out of the way, and will ? re rail? the chain back onto the small cog. It improves shifting performance, guarantees better alignment, and works with all commercially available MTB and E MTB drivetrains from Shimano to Box to Sunrace. Plus, if you ever need replacement, it will be available