Ensure your semi is ready for the journey ahead with enhanced brake safety, with the OTR 2430 Long Stroke Combination Spring Brake Chamber with Expertise Built In. 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. Engineered with a durable metal body to efficiently contain pressure and the energized spring brakes. FleetPride is your First Click in Heavy Duty.