Robert Axle Project thru axles allow modern frames to be used with axle mount trainers. Features: For use with bike trainers such as 1up, Blackburn, Cyclops, Kinetic, Tacx and more IMPORTANT: Before ordering, make sure your specific trainer will accommodate the width of the thru-axle equipped bike that you are using Measure trainer at the widest setting and measure the bike frame width at the rear hub The Robert Axle ends will extend 15mm past the frame on each side Axle shaft and axle ends are machined from 7075 aluminum and hard anodized Installed or removed using a 5mm Allen wrench Designed, built and tested in the USA