Totally unique, these Colt Vacuum Twist Nipple Suckers will keep your nipples pert and proud after creating the strong vacuum to help pull your nipple out. Place the Pro nipple sucker over the nipple and twist the cap to wind the screw up into the cap of the sucker. This will create a strong vacuum and increase blood flow around the nipple, making it erect and hard. They will also help to enhance sensitivity as they stimulate the nipple during pumping and will stay securely in place until you unwind the cap to extract the vacuum.