LiquaGen - Replacement Tank Valve for Universal Reverse Osmosis Storage Tanks (1/4" QC x 1/4") Used on pressurized storage tanks for reverse osmosis (RO) systems 1/4" quick connect (QC) makes connection to most water systems quick and easy 1/4" female NPT fits not only on pressurized tanks, but also with any other fitting using a 1/4" mal Quarter-turn lever allows you to easily shut water supply off