Ensure your semi is Ready for the Road Ahead with enhanced brake safety, with the MGM Brakes 3024 Long Stroke Combo Spring Brake Chamber. By utilizing a pressure-based chamber, this replacement component is able to apply the spring brakes as a safety measure once the internal air pressure falls below a certain level. Created with a solid metal body to efficiently contain pressure and the energized spring brakes. FleetPride is your First Click in Heavy Duty .