The pump of this model is rotary piston vacuum pump
(H/2H Series single stage), which is a kind of vacuum pumping equipment used to pump general air or air containing a small a mount of condensable steam.
It is a sort of vacuum production equipment suitable for pumping ordinary gases and a little condensable gases(for example, water vapor) with a gas ballast used. The pump must be fitted with appropriate accessories if gas is rich in oxygen, explosive, corrosive to ferrous metal, chemical reactive with vacuum pump oil. The pump can be operated singly.
It also can be as a backing pump when combined with another high vacuum pump, such as diffusion pump, booster pump and roots vacuum pump. Rotary piston vacuum pump can be used for a longer time than the sliding vane rotary vacuum pump.