Equip your semi truck to be Ready for the Road Ahead , with the Hyflow SAE-16 In-Line Relief Control Valve, a key component that prevents over pressurization of a hydraulic system. With an internal monitor, this replacement valve automatically opens to release built up pressure once it has exceeded a certain level. Crafted with a multipurpose design to be suitable for a number of hydraulic systems. FleetPride is your First Click in Heavy Duty .