Southwest Wheel Pair 10" X 2 1/4 Self-adjusting Electric Brakes with Hardware Pair of 10" x 2 1/4" self-adjusting electric brake assemblies 4 Hole Mounting for 3,500 lbs. trailer axle. Comes with mounting nuts, and lock washers Contains 1 left and 1 right brake assembly. Works with Al-Ko, Dexter, Lippert,and Quality Trailer Axles Factory Boxed.