22-MM-FEMALE X 3/8"-MALE COUPLING - Pressure washer screw couplings are used anywhere high-pressure connections are frequently assembled and disassembled. They connect to all common 1/4 inch (6.35 mm) or 3/8 inch (9.53 mm) pressure washer equipment in the industry and convert M22 metric thread size to standard National Pipe Thread (NPT) size for leak free connections. Screw couplings are easily hand tightened and are ideal for connecting hoses together.