Eaton Weatherhead C3269X8X6 Carbon Steel Fitting, Adapter, 3/8" NPT Female x 1/2" O-Ring Boss Male (Pack of 4) Adapts 3/8" NPT female end to 1/2" O-ring boss male end Carbon steel for durability and resistance to rupture under high pressure For use with LP and natural gas, refrigeration, and hydraulic applications