Kit comes with everything needed to replace trailer's drum or disc brakes for faster stopping power. GalvX coated rotors for corrosion resistance. Marine grade aluminum calipers with stainless steel pistons and slider pins. Disc brake actuator features cast ball clamp, oversized master cylinder, with back flow style solenoid installed. Includes pair of GalvX coated vented rotor disc brakes, disc brake actuator, brake line kit, and free backing solenoid. Also includes brake hoses, brass fittings and attachment hardware. Fits 13", 14" and 15" wheels. DOT 3 brake fluid not included.