Personalize your ride and your data with RED AXS E1 controls, flat mount brake calipers and the Hammerhead Karoo. Use Bonus Buttons to scroll your head unit or shift your derailleur from SRAM's comfortable, powerful and ergonomic controls. The Updated hood and lever architecture and achieved breakthroughs for fit across all hand sizes and easy access to powerful and smooth, easy braking from anywhere on the bar. The calipers are not only stiffer, but lighter too, with phenomenal pad clearance for rub-free operation. The Hammerhead Karoo GPS offers unparalleled connectivity with SRAM AXS products to allow for easier customization, better equipment awareness, and simple pairing with your groupsets, power meters, tire pressure sensors, and more. The RED AXS E1 upgrade kit is compatible with all generations of AXS derailleurs.