The Zipp Vuka Clip Aerobars w/ Alumina Evo 110 Extensions are designed to help you go faster and be comfortable. They are highly adjustable and can fine-tuned to perfectly fit rider ergonomics. The below bar mount puts riders into a lower position for aero efficiency. Does not include base bar. Specifications: Rise: 110mm Stack Height: 60mm Bar Clamp Diameter: 31.8mm Extension Clamp Diameter: 22.2mm Internal Cable Routing Yes Shifter Fitment: Plug Style Material: Aluminum Color: Black