The Shimano Tourney TY300 6/7spd Rear Derailleur has a SGS cage can handle wide range gearing and 34 tooth sprocketsShimano Tourney TY300 6/7spd Rear Derailleur Highlights-Shimano TY300 6 / 7-speed rear derailleur (bracket attachment)SIS rear index shifting13 tooth pulleys offer long service life and less noise
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