The suction cup holds the panel and the 3lb slide hammer pulls the dents out without damage to the paint work. 330mm inlet hose set with 1/4"" pneumatic connection. Working pressure 70-170psi (5-12 bar). Recommended pressure 150psi (10.5 bar). 3 x pad attachments, diameters: 60, 120 and 150mm. After connecting the dent puller to the air supply the puller creates the vacuum and sucks firmly to the body, the slide hammer is then used to pull out the dent.