A handheld vacuum pump is a device used to produce low amounts of vacuums. It contains of a cylinder with a nozzle at the end. The vacuum is drawn in from this nozzle. There is a long handle to hold the pump, which is held much like a pistol. Behind the handle, there is a piston. The handle and the piston can be moved in a scissoring fashion. When the two are moved together, then a vacuum is produced in the region connected to the inlet. A handheld vacuum pump can produce typically 25 mm of Hg vacuum pressure.