The Boston Pump Works 3/4 Nipple Cylinders - Boston Pump gives nipples a real work out. Includes two clear plastic lucite cylinders specially flared on the bottom to maintain comfortable suction. Medium 3/4 inch cylinders for use with The Boston Pump Works Plastic Vacuum Pump OR The Boston Pump Works Brass Pump. Penis Pump is not included. You will also need the Buddy Connector to attach both nipple cylinders to the pump. Made in the U.S.A by Boston Trading Company.