Swagelok Diaphragm Valve

diaphragm valve
Diaphragm valves (or membrane valves) consists of a valve body with two or more ports, a diaphragm, and a "saddle" or seat upon which the diaphragm closes the valve. The valve is constructed from either plastic or steel.
A valve with a flexible linear motion CLOSURE MEMBER that is forced into the internal flow passageway of the BODY by the ACTUATOR. Pinch or Clamp valves and Weir-type valves fall into this category.
A device consisting essentially of an automatic valve actuated by means of the application of fuel pressure upon a flexible diaphragm.

swagelok
The Swagelok Company registered trademark brand name tube fitting providing UHV compatible connections on fractional inch tube sizes; uses a compressible ferrule; requires clean tube end only.
Swagelok is a privately held international company, focusing on the manufacture and sale of gas and fluid systems components, such as compression fittings, valves, tubing, and gauges. It was founded in 1947 by Fred A. Lennon in Solon, Ohio, where its headquarters remain.