For high pressure hydraulic systems. Swivel adapters are rated up to 10,000 PSI, depending on size. NPSM X NPTF thread for metal to metal seal. Max. PSI 10,000, Swivels Yes, Fitting Size in. 3/8 x 3/8. Allows users to take a preassembled hose and connect it to your connection-specific machinery Adapters also help to correctly route hoses and make replacement easier