Auto Shut Off Valve set to trigger at 90 percent - System automatically shuts off when the tank pressure reaches 90% of the incoming line pressure. ASO ASV Comes with 1/4" OD Tube John Guest Speed Fit quick connectors. Made for use with systems that have a pressure booster pump such as aAquatec ER-1000 permeate pump. Adding a permeate pump to a system with a standard auto shut off valve works fine. But changing the auto shut off valve to one that triggers at 90 percent of incoming line pressure will increase the holding capacity of the tank and provide a faster flow rate when dispensing water from the faucet. • Increases flow and pressure • Increases storage tank capacity • Great for ice maker supply • Improves water quality • Extends membrane and diaphragm life • Reduces TDS creep • High pressure side is labeled with "In & Out". Low pressure side is labeled with "Tank". Low pressure side in & out correspond to the same orientation as the high pressure side. One side has markings "In" & "Out". The other side of the valve body has 2 markings "Tank". "Tank" is the low pressure side and "In" & "Out" are the high pressure side. Also, the "In" and & "Out" location is the same orientation on both sides. • Hydronamic # ASV-ERP-JG ASV-100 Grey body is 90% and ASV-100 white body is 60%. We ship only the grey body 90% valve for the ASV-100.