Progressive Suspension has designed the GP3 series pump to provide the most convenient and accurate method to regulate the air pressure in your pneumatic shock or fork systems. Features a flexible hose equipped with a no-loss connector that attaches to any standard Schrader Valve. This allows you to precisely inflate and deflate your shock or fork with no air loss from the system when disconnecting the hose. The GP3 pump has a system that allows the user to regulate the rate and amount of air deflated from the system depending on the pressure inside the system and how far the pressure release button is depressed.