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.The RED AXS Upgrade Kit includes - RED brake/shifter eTap lever pair, flat mount 2-piston 20mm offset brake caliper pair, and Hammerhead Karoo GPS bike computerOne finger braking from the hoods or the drops for less fatigueAXS enabled for easy setup, personalization, and reliabilityBonus Button provides ANT+ device control or auxiliary shift optionOptimized hood shape fits the widest range of hand sizesCarbon brake lever for light weight and textured shift paddles and hoods for control and comfortReach Adjust offers a custom fit for more hand sizes and Contact Point Adjustment allows riders to personalize brake engagementIncluded Hammerhead Karoo GPS bike computer 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 moreItem SpecificationsBrake Caliper TypeFlat MountBrake Lever ActuationHydraulicBrake TypeDiscDrivetrain Speeds12Drivetrain Speeds13Front Der/Shifter CompatibilitySRAM eTap AXSRear Der/Shifter CompatibilitySRAM eTap AXS SRAM RED AXS eTap Upgrade Kit E1 Kit-In-A-Box Road Group UPC: 710845905148