New Hydronamic Engineering 80% automatic shutoff valve (ASV100-RED or ASV-ERP-JG) specifically designed for reverse osmosis systems with permeate pump, to minimize TDS creep at startup. The valve is manufactured in the USA from virgin polypropylene using injection molding and very well constructed. The valve operates off a pressure signal and will automatically shut off water supply when tank pressure is approximately 80% of supply pressure. Retain the benefits of a permeate pump without sacrificing system pressure common with other ASO valves. Supplied standard with 1/4” QC x 1/4” MNPT John Guest male adaptors. Connections – 1/4″ John Guest push to connect fittingsValve Shutoff pressure – 80% of water supply pressureInstallation instructions providedIncludes two (2) 1/4” QC x 1/4” stem elbows