True blue solenoid valves automatically shut off flow of highly corrosive and ultra-pure liquids. They can handle acids, caustics, solvents, chlorine solutions, sodium solutions, deionized water, reverse osmosis water, brewery processes, etc. and do not require pressure to aid in opening the valve. 2,000,000+ cycle life (tested under laboratory conditions). Valves are spring return normally closed and direct acting with a heavy duty push-pull plunger design. There is no minimum pressure required for operation. The PTFE bellows shaft seal eliminates the need for an elastomer seal which can weaken as a result of chemical attack. Provides low friction sealing, non-sticking operation, and million cycle design. The bellows design also allows a stock valve to be used for vacuum or pressure. A poppet seat ensures bubble-tight shutoff. Patented Fail-Dry vented design. No metal parts in wetted area. Suitable for all types of solutions. Molded corrosion-resistant coil assembly. IP-54/Nema 4 water and dust tight enclosure. Optional coil connector light indicates when valve is energized. Valves are not recommended for use with pressurized dry chlorine gas. Viton seals. W20 Coils are equipped with 1/2" DIN connector. Polypropylene body material. Valves are rated for full vacuum. 20 watt coils are continuous duty. All valves individually inspected and 100 percent tested to insure reliable operation. All-purpose design permits phase-out of multi-type valve stocking.