Fine tune your position on Profile Design Aerobars with their Aerobar Bracket Riser Kit. Compatible with Profile Design's T+ Carbon Series, T+ Aluminum Series, and ZBS Aerobars, the Riser Kit allows the armrests and extensions to be raised together in 30mm to 70mm height options. Compatible with following Profile Design Aerobars: T+ Carbon Series, T+ Aluminum Series, and ZBS Aerobars Kit includes risers and bolts specific to the kit size Available in 30mm, 40mm, 50mm, 60mm, or 70mm rise options Clamp diameter: 31.8mm