A water aspirator is an inexpensive and dependable source of moderate vacuum in the laboratory. As the water rushes past a side arm aperture, a partial vacuum is formed. The lowest approximate pressure that can be achieved with this device is 10 mm of mercury or 10 torr.
When you are pricing aspirators remember some models that sell for less will not have a built-in check valve. Both of the models we sell do; thus eliminating the need for a trap. Water inlet diameter is 3/8" NPT.