Product Details: The Bendix 4.75" TP-3 Tractor Protection Valve is designed to protect the tractor air brake system in the event of a trailer breakaway or severe air leak. This valve can be mounted on the rear of the tractor cab and is stringently evaluated to ensure reliability performance and high efficiency. It is used to shut off air to the trailer before disconnecting the lines. This valve is a must-have for any tractor air brake system, providing peace of mind and safety for the driver. FleetPride is your First Click in Heavy Duty®.