Stainless Steel Pressure Washer Couplerquick Connect Plug3/8 Inch Male Npt Fitti by | Jul 22, 2026Convert 3/8″ male quick disconnect plug to 3/8’’ male NPT fitting. Material: Stainless Steel.3. It is made of stainless steel. It used in a lot of situations where high pressure connections are frequently assembled or disassembled.