SRAM's Red Rear Derailleur boasts a winning combination of aluminum, titanium, carbon and ceramic materials for awesome efficiency, flawless shifting and feathery weight. Gear changes are faster and more precise than ever before thanks to SRAM's Exact Actuation technology and a titanium main spring. Plus, the ultra-smooth ceramic pulley bearings and resilient carbon construction ensure this beauty is super light and reliable for amazing shifts every time.