After attaching the K-Air II to the end of your K-220 or K-20 K-Pump, which is held in place by a friction lock, just start pumping. Once you reach the appropriate PSI for your inflatable, all excess pressure will be bled off letting you know when to stop. It’s that simple! We’re not done though, if you have the luxury of having an air compressor near where you are inflating your craft, such as at a service station, we have included an adaptor with a standard Schrader valve as found on car and bike tires. This allows you to safely inflate and go in a fraction of the time, saving your muscles for the water!