Universal 12T Bike Derailleur Pulley - Rustproof Rear Derailleur Jockey Wheel for Road Bikes, Mountain Bikes, Folding Bikes & E-Bikes | Perfect for Smooth Gear Shifting & Enhanced Cycling Performance

Features: Aluminum alloy guide wheel body, lightweight, high strength, anti-rust and durable. The ceramic bearing has good performance in rolling smoothly with great stability, low chance of getting chain stuck. Compatible for most of rear derailleur on the market and support 8/9/10/11 speed. Fit for 4/5/6mm roller screw shaft with the screw shaft adapter. A must-have replacement part for your bike. Specification:Material: Aluminum Alloy Body + Ceramic BearingColor Options: Black; Red; Blue; TitaniumType: 12TFit for 4 / 5 / 6mm roller screw shaftSupport Bike Speed: 8/9/10/11 SpeedDimension(Dia x T): Approx. 4.6 x 0.5cm / 1.8 x 0.2inchMiddle Hole Diameter: Approx. 6mm / 0.24inchWeight: Approx. 23g Packing List: 1 x Bike Rear Derailleur Pulley1 x 4mm Screw Shaft Adapter1 x 5mm Screw Shaft Adapter