Sram Uuniversal RD HangerFeatures The Universal Derailleur Hanger (UDH) consolidates thousands of mountain bike derailleur standards Designed to rotate rearward in the event of impact, and features the ability to re rail the chain back onto the small cog It works with all commercially available MTB and E MTB drivetrains from Shimano to Box to Sunrace Unparalleled derailleur protection. And perfect alignment. Guaranteed Specification Material Aluminium Compatible Models all