Zipp's Vuka Extensions are made of ultralight, stiff carbon and come in different bends so that you can find the model that optimizes your aero position and maximizes your speed. The Straight extensions place you as low as possible, while the Race and Ski-Tip models have more bend for your wrists. Then, for a seamless junction between your shifters and the extensions, the Race Vuka Shift has built-in mounts that let you screw your shifters directly to the extensions. They accept Zipp's R2C Aero shifters and SRAM's 900 TT and 500 TT shifters. All the extensions have internal cable routing and gradations to make adjustments easy.