The Steel Hitch provides the critical connection from your Burley Trailer to your bicycle. The hitch installs easily on the rear skewer of your bike, and then stays attached so the Burley can be connected at any time. If you’d like to swap the Burley from bike to bike, pick up a couple spare hitches and install them on the extra bikes so the hitch doesn’t need to be un-installed when swapping bikes. Steel Hitch The Steel Hitch will fit most bikes out of the box, but if you have a breezer style dropout or another unusual setup, you may require an adapter. Works with disc brake and full suspension Does not fit Breezer style dropouts Fits QR axles and solid axles up to 12mm 12mm Thru-Axles will require a alternative axle from the RobertAxleProject.com. This replacement axle has external threading to accommodate the installation of our axle mounted hitches. If you are upgrading from a Classic Hitch to a Steel Hitch, you will also need to purchase a Flex Connector: Part # 950038 (square tow bar) or Part # 950037 (round tow bar).