Body: clear anodized aluminium.
Bonnet: powder-coated aluminium.
Cap: powder-coated aluminium.
Spring: stainless steel.
Poppet: hard-coated aluminium.
Screw: hard-coated aluminium.
Poppet Seal: Nitrile.
The 199ASV installs on the top of an aboveground storage tank with a suction rod on the inlet and the fuel supply line (to a remote pump) on the outlet of the valve.
A poppet in the valve remains normally closed, isolating the tank from siphoning. When the remote pump is activated, it overcomes a factory-adjusted spring set to a predetermined hydrostatic head pressure and allows flow of fuel out of the AST.
An internal pressure relief valve helps absorb thermal expansion in the fuel supply line.