iSpring Quick Connect Fitting Reverse Osmosis Drinking Water Fixed Elbow Fitting, 1/4 In. NPT x 1/4 In., 2 Pack in the Push to Connect Fittings department at Lowes.com
QuickFitting 3/4 Inch Push On Coupling | Patented Design for Superior Sealing | Push to Connect Brass Plumbing Pipe Fitting | for Copper, PEX and CPVC | 5-Pack - Amazon.com
Brass Faucet Standard Adapter Washing Machine Water Gun Quick Connect Fittings 1/2" 3/4" Threaded Nipple Joint Garden Irrigation - AliExpress
John Guest Speedfit push to fit Quick Connect Fittings