Shimano Tourney Rear Derailleur RD-TY300 6/7 Speed SGS Direct Mount Shimano rear derailleur, suit 6-7 speed bicycle freewheel Smooth shifting, easy and fast to install, large guide wheel, low noise Long cage tourney derailleur, compatible with 11T high speed gear B tension adjustment screw for simple adjustment 100% Shimano, excellent quality products, superb customers care, warranty: 24-month