Product Details: Prepare your pneumatic system for the long road ahead, with the OTR 1/8" NPT Rapid Dump Air Suspension Valve with Expertise Built In™. This replacement part regulates the volume of air throughout your hydraulic system, thanks to a pilot-operated mechanism that allows for in-line plumbing of air spring lines. Engineered for use with active and idle heavy duty vehicles. FleetPride is your First Click in Heavy Duty®.