Self-Adjusting Electric trailer brake assemblies that measure 12-1/4" X 3-3/8" with brake pads designed for utility trailers, travel trailers, horse trailer, motorcycle trailers, and more. These brakes are rated for 8,000 lbs and have a 4-bolt mounting flange bolt pattern. This product is compatible with most manufacturers and comes with a limited 1-year warranty. 2 pack (1 left and 1 right) or 4 pack (2 left and 2 right)