Welcome to toedge's shop [toedge] Bike Ceramic Bearing Derailleur Pulley Alloy Rear Derailleur 12T Guide Wheel Description: 100% brand new and high quality Specification:12T Weight: approx 11.5g Material :AL7075-T6 CNC machined Installation dimension:6MM/5MM/4MM Bearing :ceramic bearing Color: black ,red ,blue,gold,silver Feature: it is cnc machined by AL 7075-T6 round rod ,finished machined by diamond cutter,with diamond metal texture and good abrasion resistance index , it adopts imported Japanese steel bearing,rotating without resistance ,it greatly decreased frictional resistance,and increased cycling efficiency, the design inreased bike derailleur shifting speed ,it causes no noice when shifting speed k and prevent bike chain falling . Package: 1 pc 12T guide pully