FARR Aero Gravel Alloy – Various WidthsTaking what we saw happening with our Aero Bolt On and their popularity with the Gravel Adventure crowd, we wanted to create a 1 Piece design that offered the extra hand positions and comfort in an affordable package. Enter the AERO GRAVEL ALLOY handlebar. Integrated Aero Add On Provides Extra Hand Positions Ideal for Gravel Bikes Touring Adventure 31. 8mm Clamp Diameter Alloy 6061 T6 Material Ergo Top Profile for Comfort Moderate 25 Degree Flare