Bike Guide Wheel - Week Eight Aluminium Mountain Bike Jockey Wheel Rear Derailleur Pulley 11T for Shimano SRAM Gold Anodised CNC machined bicycle jockey wheel with fully rubber sealed bearing for center bolt derailleurs. 11 teeth bicycle rear derailleur accessary Made of CNC aluminum alloy, lightweight and durable. A necessary accessary for your bicycle. Stainless Steel bearing for ultra durability