Oblon, Spivak, McClelland, Maier & Neustadt
Gas pressure gage
 A gas pressure gage connected to a pressure tank includes a solid stem body which has a gas channel extending from the first end to the second end thereof. The solid stem body further includes a cavity which communicates the gas channel with the exterior of the gage. A spring-biased piston rod disposed in the cavity, provided with a sealing member, seals the gas channel unless the gas pressure in the gas channel exceeds the force of the spring member, or the piston rod is operated manually. 
G Y Y
G01L Y10T Y10T
inventional additional additional
Tien-Tsai
Huang