Made from corrosion resistant 316 Stainless Steel. This fitting is 3/8" NPT (National Pipe Taper) to 3/8" NPT. This hex coupling has a male connector on both ends. It can be used as a pipe fitting. This hex coupling can be used for oils, air, water, liquids, steam and gasses. This hex coupling is stainless steel. Stainless steel is known for its chemical resistance. It is 37mm (1.48") end to end. The width of the hex nut is 5mm (0.2").