Shimano sora 3500 9 speed rear mechsora derailleurs feature an advanced light action for low friction shifting up or down the block featureswide link design for increased rigidity and precise gear shifts11 tooth pulleys for reduced pulley wear and chain noisepulleys feature sintered alloy bushings for smooth running performancecompatible with 9 speed drivetrainsspecificationscassette compatibility9maximum sprocket32t14tminimum sprocket25t11tmaximum front difference 16t short 20t m