Feature: Workmanship is very detailed, smooth burr-free, precise size. Helpful when the 10 speed, 11-speed flywheel upgrade to 42T - 50T. Bicycle speed to the maximum flywheel, may rub onto the wheel. At this time, you just need to add this product in the original bicycle real dial hook the converter, you can easily solve the troubles you encounter.
Specification: Material: Aluminum alloy Size: App. 4.5cm*2.3cm Hole Diameter: Approx. 1cm / 0.4inch Screw Diameter: approx. 1cm / 0.4inch Color: As the picture show