Get your semi Ready for the Road Ahead with enhanced control of its spring brakes, with the OTR 1/2" Reservoir Spring Brake Control Valve with Expertise Built In. With a specialized design, this replacement control valve monitors the air pressure in a brake mechanism, engaging the spring brakes once pressure is lost. Manufactured with durable materials to withstand the daily demands of commercial vehicles. FleetPride is your First Click in Heavy Duty.