Prepare your semi to be Ready for the Road Ahead , with the MGM Brakes 3030 Long Stroke Spring Brake Chamber that provides enhanced brake safety. Due to its pressurized inner chamber, this replacement component is able to apply the spring brakes as a safety measure once the internal air pressure drops below a certain level. Constructed with a rugged metal body to efficiently contain pressure and the energized spring brakes. FleetPride is your First Click in Heavy Duty .