Complete Disc Brake Kit comes with everything needed to replace your trailer's drum brakes or adding vented rotor disc brakes for faster stopping power. Includes a disc brake actuator that features a cast ball clamp, oversized aluminum master cylinder pre-assembled with a backflow-style reverse lockout solenoid, a pair of corrosion-resistant GalvX-coated vented rotor disc brake using marine-grade aluminum caliper with stainless steel pistons and slider pins, brake hose kit includes 240", 76" and 24" DOT flexible brake hoses with brass fittings and attachment hardware. 10" kit fits 13", 14" and 15" wheels. Each kit contains: - 2 Disc Brake Assemblies- 1 Disc Brake Actuator- 1 Brake Line Kit for a Single Axle Trailer.