VacuGlide’s suction power is adjustable via an allen screw that allows you to change the length of the stroke of the vacuum producing piston. To adjust it, you loosen the allen bolt, slide it to your desired location, and then lock it down again. But if you forget to lock down the allen screw after loosening it, you’ll get a not very nice clunking sound and a lot of friction! This video shows you how to tighten the allen screw down again to enjoy your pleasure silently.