... valve are improved from 2W/2S valve, they are 2/2way, direct action type. Using some special area. ... at zero differential pressure.1)port size: 1/8 " ~2 "2) Working Medium: air, water, oil, gas3) Action Type: ... Body: 2W: Brass or 2S:Stainless Steel5) Valve Control Style: NC(normal close)6)Orifice Size:16,20, ... %Material of BodyStainless SteelMaterial of Oil SealXNBR 2-way Explosion-proof solenoid valve