Brennan Adapter. zinc plated steel. 1/2 female pipe swivel 1

For connecting those two thread types, it matches up a 1/2-14 female NPSM swivel on one side with a 1/4-18 male NPTF on the other. The female swivel thread is to SAE J514 and the male NPTF side is to SAE J476.

This adapter is rated for a maximum dynamic pressure of 5000 psi, so it should be suitable for your system, assuming the pressure remains consistent.

Rated at 5,000 psi maximum dynamic pressure, so it's built for serious hydraulic work. The zinc-plated steel construction gives it solid durability under sustained load, and the NPTF male thread on one end gives you a reliable pressure-tight seal without relying on sealant tape alone. For continuous-duty hydraulic lines operating within that pressure ceiling, it should hold up just fine.