TRP EVO Rear Derailleur. Features: Integrated Hall Lock Lever stabilizes the rear derailleur and can be turned on or off to facilitate easy wheel removal/service Horizontal parallelogram stabilizes the rear derailleur while riding over rough terrain Instant, silent clutch prevents unwanted chain slap and noise Carbon fiber outer cage 12T/14T sealed bearing pulleys Specs: Model:EVO Speed:12sp Cage:long Max Tooth Count:53T Weight:301g Color:black/gold