Malida Automatic Shut Off Valve with 1/4 Inch tube Quick Connect Fittings For RO Reverse Osmosis QC fittings,1/4Inch fittings Automatic Shut-Off Valve 1pcs, Quick Connect Fittings This a replacement part for a standard Reverse Osmosis (RO) System All tube connections are 1/4" with "in" and "out" labeled on the top