While trying to connect a new water supply line to a 1984 valve, neither the 1/2" nor the 3/8" will fit. Is there such a thing as a 3/8" INSIDE diameter supply line? Or an adapter we can use?
Also, while changing out a shower arm, part of the screw on part broke inside the pipe. What can get this out?

Thank you.

There is a 1/2 O.D copper pipe.. think that may be what you have... rare in my parts but
1/2" compression (soft copper) has been around a long time. Here, I would recommend a 1/2"O.D compression by 1/2" copper straight adapter to adapt to 1/2" copper pipe. That should do the job.

The shower arm... when this has happened to me I have used a very small flathead screwdriver and a small hammer and I have simply hit the shower arm thread lightly (and downward) and this has dislodged every time... be careful not to hurt threads in shower riser (elbow).

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