"The Shimano Deore RD-M7200 brings SHADOW ES chain stabilization and a wedge-shaped low-profile body to 12-speed mechanical drivetrains. A steel pulley cage adds extra strength to an already robust structure, and covered pulleys with a solid cage keep trail debris clear of the drivetrain. What Our Gearhead® Experts Are Saying:""The steel cage has taken rock strikes that would have ended a ride on a lighter derailleur. It bends back into shape and keeps shifting; that makes a huge difference on a long day in technical terrain."""