The Giant Contact SLR Aero Propel Carbon Road Handlebars are made from an ultra-lightweight carbon construction and an aero contoured top profile. Giant Contact SLR Aero Drop Bar (Propel Disc only) is for when you want every aero advantage available. Stiff, light and fine tuned to reduce vibration. These handlebars are dedicated to the Giant Propel Disc series and requires Contact SL or Contact SLR aero stem for compatibility - if you are unsure, please speak to your local Giant retailer.