Amazon.com: PureSec 3/8 inch Tee Connector Push to Connect Fittings Plastic Quick Fitting for water purification&RO System (5, 3/8" Tube O.D.X3/8" Tube O.D.X 3/8" Tube O.D.) : Industrial & Scientific
Watts 3515-10 1/2 IN CTS Quick-Connect Coupling, Plastic