TT1090-R2C: Return-to-center design for optimized aerodymamic efficiency plus a 40-degree angle adjustment to align with different aero-bar profiles and up to 3-indexed rear shifts with a full-sweep front. T900/500: Friction front shifter with a 3-position stop for release positioning and a 10-speed SRAM-indexed rear shifter. Exact Actuation cable pull is only compatible with SRAM road (and 10sp mountain) derailleurs. Aluminum housing with internal, conical expander mounting system. Bottom-exit, external cable routing to maximize fitment with aero bars. Includes housing and Teflon coated stainless steel cables. Fits 19.2-22.5mm internal bar diameter with a minimum depth of 35mm. TT1090-R2C: minimized carbon shift lever with black anodized cover and red cap, plus titanium hardware. TT900: carbon shift lever with black-anodized cover and red cap. TT500: aluminum shift lever with black-painted cover and red cap.