Flair-It 16874 RV Fresh Water Plumbing Coupling 3/8" PEX x 1/2" FPT
SharkBite 3/8-in PEX (1/2-in O.D) x 1/2-in NPSM Brass Female Swivel 90-Degree Elbow in the PEX Pipe, Fittings & Specialty Tools department at Lowes.com
Us Market Cupc Coupling 3/8" Pex*3/8" Brass Pipe Pex Fittings - China Brass Fitting, Pex Fitting | Made-in-China.com