Ei Trailer Brake Assembly Electric Trailer Brakes 12" x 2" - 2 right & 2 left 5200 6000 7000 lb axles Dexter Style Backing Plate Axle Size - 5200-7000lb Brake Flange - 5 Bolt Fits Spindle - #42 eCustomhitch Carries a Variety of Electric and Hydraulic Trailer Brake Parts