AFW ASV90 ASV90-14Q 90% Auto Shut Off Valve for Reverse Osmosis ASV for RO with permeate Pump, 1/4", Gray Best valve to use with a permeate pump on RO (reverse osmosis) system ASO ASOV Allows storage tank to fill with more water! Water delivered from storage tank under higher pressure More water capacity! Use with a permeate pump for best results. High quality valve, reliable, long life! Quick connect 1/4" fittings