1、Used for lengthening the rear derailleur. Suitable for 40T/42T/46T/50T mountain free wheel or 32T/36T flywheel to lengthen the flywheel speed, and change speed more smoothly. 2、For rear brakes. Suitable for 40T/42T/46T/50T downhill pulley or 32T/36T flywheel, extend the flywheel speed, more smooth. 3、Lock screw material is 7075 aluminum alloy, lock torque is greater, with rolling groove. Lock firmly, solve the problem of vibration release. 4、Anodized surface color, resistant to weather and sun, bright color, make your riding more exciting, uniform color, better look. 5、Removing the limit point, it can adjust the rear derailleur flexibly, make the speed change more correct, improve the response speed of speed change, and solve the problem of slow speed change. 6、The surface is designed with rolling groove to increase friction. Condition: 100% Brand New Item Type: Derailleur Extender Material: 7075 aluminum alloy + hand polishing Purpose: to extend the Derailleur Hanger Applicable: upgrade 34-52T flywheel (used in mountain bicycle/road bike) Recommended torque value: 15-20n.m Application: used for lengthening the Derailleur Hanger, suitable for 40t/42t/46t/50t mountain free wheel or 32t/36t flywheel, to lengthen the speed of flywheel and make the speed change more stable 1 Set of Derailleur Extender