Precision-engineered PR-4 pressure protection valve, designed to maintain 85 PSI nominal closing pressure for reliable air brake system performance in heavy-duty applications Includes 1/4-inch NPT supply and delivery ports for compatibility with standard commercial vehicle brake plumbing Made with high-grade materials for long-lasting durability in fleet, vocational, and linehaul trucks under harsh operating conditions Direct OE replacement for a wide range of part numbers from Bendix, Haldex, Navistar, Mack, Wabco, Automann, and more Package includes (1) 85 PSI PR-4 protection valve by World American – meets or exceeds OEM performance and safety specifications