Material Brass and rubber gun adapter and quick connectors, brass and stainless steel spray nozzles, exquisite craftsmanship. Pressure washer gun adapter model only compatible with Krcher K2, K3, K4, K5, K6, K7, female quick connect and spray nozzle only 1/4", please note the size before connecting. 1/4" Quick Coupler Design - The 1/4" internal thread quick coupler is made of brass which can prevent rust and corrosion. 1/4" quick release design allows for faster application, easy to connect and disassemble. High efficiency Adapter connects to pressure washer spray gun with the quick coupling and the female connector is connected to the 1/4" foam gun. Pressure washer accessory Conversion to 1/4" quick coupling with internal thread . One end connects gun to pressure washer or foam cannon tips with 1/4" connector. The other end is inserted into the gun and twist the adapter clockwise. Scope of delivery: 1 piece 9.1*3.1cm