Do it Best 1/2 in. Nom Copper x 3/8 in. OD Union

Straight connector. 1/2 nominal 5/8 O.D. copper compression to 3/8 O.D. tube.
Hartville Hardware offers so much more than a traditional hardware store, from grills and outdoor furniture to Carhartt clothing and John Deere tractors.

Everbilt 1/2 in. Copper Pressure Cup x Cup Union Fitting C633WHD12 - The Home Depot

Brass Compression Fittings for Potable Drinking Water

Brass Copper Ferrule Tube Fitting, Union Compression Coupling 1/4 5/16 3/8 Compression Elbow Tee - China Brass Elbow, Tube Fitting

Large Selection of Copper Sweat Fittings and Adaptors

5/8 OD Compression (1/2 Copper) x 1/2 PEX Brass Adapter (Lead Free)

LTWFITTING 1/2-Inch OD x 3/8-Inch OD Compression Reducing Union,Brass Compression Fitting(Pack of 25) - Compression Fitting Ferrules

LTWFITTING 3/16 in. O.D. Brass Compression Coupling Fitting (10-Pack) HF62310 - The Home Depot

Pipe Fittings - Stainless Steel Unions - 3/8 NPT 150# 304

BrassCraft 3/8-in x 1/2-in Compression Adapter Fitting in the Brass Fittings department at

PROCURU 10-Pack PushFit Angle Stop Valve 1/2 Nom x 3/8 OD Comp, Quarter-Turn Push-to-Connect Brass Shutoff Valve for Copper, PEX, CPVC, PE-RT, HDPE Pipes (8X8012-11T) : Everything Else

64X8 by Danfoss, Compression Fitting, Union Tee, 1/2 Tube OD

Everbilt 3/8 in. Flare x 1/4 in. MIP Brass Adapter Fitting 801539 - The Home Depot

7/8 TYPE L - ACR Hard Copper 20 FT Lengths — COPPERTUBINGSALES

1/2 to 3/8 Reducer, Vfauosit 3/8 to 1/2 RV Faucet Adapter Brass Compression Fitting Faucet Supply Line Adapter for Plumbing Water Hose 2 Pieces