It either fits because it's the right diameter and the right thread pitch and the right thread direction... Or it doesn't.

If it's not right, don't try to half-ass it.

Since it's the tub drain and I can monitor the leak which is in an unfinished basement so dripping of water won't hurt anything... I attempted to half-ass it for the moment and see what comes of it. Next is a plumber.

Looks like a cheap import junk that has poor quality control. Buy something solid brass and try again.

Hi, Take the old one to a plumbing shop to get one that works for you. You have to have the same size and treads per inch. Try the old one in a fitting if it fits then get a new part you need.

Good Luck Woodbutcher

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