No nearby source of running water? No worries, with the Bosch Self Priming Kit you can draw water from a standing source such as a water can, a dam or a trough. Simply submerse the hose to purge as much air as possible before connecting to the inlet of your pressure washer. Place the shielded one way valve into a source of water as deep as possible, turn on your pressure washer and pull the trigger. Make sure you don't have anything connected to your hand piece at this point to aid in the purge. Once there are no longer any pressure fluctuations, connect your lance and chosen tip and you're ready to clean.