Sunrace RDM57 M50 Rear Derailleur 7/8 SpeedThe Sunrace RDM57 M50 Rear Derailleur is a perfect replacement for your worn out 7/8 speed Shimano Rear Derailleur. This is the Direct Mount version with an optional hanger. This Rear Derailleur is made with Engineered Polymer and Steel. This is not compatible with Shimano MegaRange cassettes. This weighs only 354g. The Shimano Equivalents are RD-M360, RD-M410, RD-M310, RD-TX75, RD-TX55, RD-TX35, RD-TZ50.4710944247183