Outfit your semi with enhanced control of its air brakes, with the OTR 4" MV-3 Style Manifold Dash Valve with Expertise Built In™. To regulate the amount of pressure in the air brake system, this replacement part features an adjustable valve that either blocks or releases compressed air. Fashioned with durable components and a quality construction to ensure long-term reliability. FleetPride is your First Click in Heavy Duty®.