Vampire Pumps draw a vacuum of 27 inches of Hg
(Mercury). The patented tube coupling device accepts any size sampling
tube (with an outside diameter of 3/16" through 5/16") without changing
The sampling tube is inserted through the coupling device until the lower end extends below the top of the sample bottle.
the knurled knob is turned to tighten the seal, the vacuum will draw
fluid directly into the bottle without coming in contact with the pump.
This patented feature allows multiple samples to be taken without cleaning the pump between samples.
Yellow Nylon Head Equipped Vacuum Release Valve