Lippert 296649 10'' x 2.25'' Left Hand Electric Brake Assembly Self-adjusting brakes provide optimal brake performance since they self-adjust at every forward stop Standard electric trailer brakes need to be adjusted by a service professional every 3 months or 3,000 miles Brake self-adjusts at every forward stop to ensure accurate braking Fits 3,500-pound wheel hub capacities Brake measures 10 X 2.25 and has a 4 bolt pattern