Product Details: The Bendix QR-1 Series 3-1/4" Die Cast Zinc Air Brake Quick Release Valve is designed to provide reliable and efficient air brake control. This valve is made of high quality durable material for an extended lifespan and delivers within 1 psi of control pressure to the controlled device in the standard configuration. It consists of one exhaust port, two delivery ports and one supply port. The valve features a 3-1/4" die cast zinc body with a stainless steel spring and a brass poppet for superior performance. It also comes with optional noise reducing foam crossers or silencers. This valve is ideal for use in air brake systems and is sure to provide reliable and efficient performance. FleetPride is your First Click in Heavy Duty®.