Quick rooftop bike loading in seconds. Accommodates most bikes regardless of frame design, suspension, or wheel size. Xadapt1 required when used on Aero bar.RQL Ratcheting Quick Load System. Fits Wheels from 20 29.Fits tires from 1 2.6 wide. Xadapt1 required when used on Aero bar. Load bike in 10 seconds or less!. No wheel removal No contact with frame.Mounts to Thule and Yakima load bars. Thule One KeyTM System Compatible. This carrier requires the use of Xadapt1 when using our Xsporter or rapid aero bars.