Moving away from the cock, why not use your vacuum pump on your nipples too?
This pair of cylinders are available in two sizes:
Small - 0.75" x 2"
Large - 1" x 3"
Please note: You will either need the Two Way Pump Connector Hose to gain the same pressure on each nipple, or two pumps to allow differing pressures between nipples. These are sold separately.
If you have your own pump/s, you may need one or two coupling/s. If so then please select below.