brand new and high quality Features: Made of high-quality Sai Steel material by fine process with durable and tear resistant characteristics, has long life. Durable and light-weight, easy to install. Apply for most rear derailleur in the market, support 8-12 speed. Bicycle wheel with fully sealed bearing for center bolt derailleurs. Pulley for Jockey Wheel only, other accessories demo in the picture is not included. Specifications: Compatible Models: shimano-compatible/sram, etc. Compatible Speed: 11T (8-speed, 9-speed, 10-speed, 11-speed) 12T (10-speed, 11-speed, 12-speed) Material: Sai Steel Optional Size: 11T, 12T 11T Size: Length: app.4.1cm/1.61in, Thickness: app.0.81cm/0.32in 12T Size: Length: app.5cm/1.97in, Thickness: app.0.83cm/0.33in Color: Black Optional Teeth: 11T, 12T Optional Style: A, B, C, D, E Quantity: 1 Pair Note: No retail package. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package includes: 1 Pair x Pulley for Jockey Wheels