Thread gauge / chaser?

[oldgoaly]

I've called these thread guides, but have seen other names?This was from a the junk box the wive got last week. A could of days in phosphoric acid solution and a coating of satin clear acrykic. They will be kept by one of my Barnes treadle lathes.

No name or markings that I can see.

[lptools]

Jeweler's Die Stock??

[bill300d]

Although not exactly a screw plate they are sometimes called such. I think lp's answer is probably the better answer
.

[oldgoaly]

I don't know any jewelers, knew one guy who bought and sold old jewelry he went into the witness protection program. Long story!
screw plate did bring up some similar looking items that were listed as "watch maker's" die/threaders
pic is of a German made version I have.