If you have been given a small cube box with an adaptor in it, you will need to use PTFE tape around the brass thread of your Short Trigger Gun approximately 5-8 revolutions. Screw this adaptor onto your Short Trigger Gun and tighten. If you are using an M22 adaptor, simply PTFE tape the brass thread on the end adaptor. Proceed to click in your pressure washer's hose via the adaptor or screw it in via the m22 adaptor. Screw the gold quick connector adaptor onto the spray end of the short trigger gun tightly before inserting a coloured spray nozzle.