Square Gas Valve . Quarter turn straight valve 300,000 btu in satin chrome: Straight valve in flat black: GENEBRE Gas square valve, FM Angle ball valve for gas, FM from www.genebre.com Telescopic extension stems can also be furnished with position indicators for buried service (patent pending), as illustrated here, the. Quarter turn straight valve 300,000 btu in satin chrome: This tutorial will demonstrate how to turn off the gas on any of your household appliances.