These suction cups create a vacuum seal against the skin, which can be released with the metal screw near the hand pump. The cup holds a powerful 10 setting reachargable bullet vibrator that can be removed and comes with a charging cable. The cup has very soft silicone tendrils inside for stilumation. This can be used as a clit/peen pump, nipple toy, etc. as long as the cup can seal against the skin!