"tube coolers"

Economy blue hand vac pump for experiments in air pressure, vacuum filtration, and leak checks.

Demonstrate many exciting low-pressure phenomena in your physical science classroom.

Sturdy Hand Pump Features Hose Connectors For Vacuum And Pressure

Welch DuoSeal is a single-stage pump with metal vanes and motor mounted on steel base with rubber feet.

More economical than an electric vacuum pump.

Welch DuoSeal Two-stage Pump operates at a low rpm, runs cool, and reaches maximum vacuum with less back streaming.