Keep your nipples stiff and sensitive with this nipple erector set and experience pumping pleasure! To start, take the pump with the smallest opening. Slide the rubber ring of your choice over the opening and place it on your nipple. Squeeze the air reservoir until you reach the desired result. Slide the rubber ring around your nipple to keep it hard and sensitive. Repeat these steps with your other nipple. To get the nipples even bigger, use the pump with the wider opening. Have fun! Dimensions 4.33 inches by 5.12 inches by 1.97 inches. Weight 2.33 ounces.