Can anyone identify this tool?

[diopter]

95 % sure it's not for guns, but what?
Watches?

Both ends have a flat spring I presume for retention.

 

[qtip]

Looks like something my mom had for fixing her sewing machine when I was a kid.

 

[53Izzy744]

 

[FLHTCUI]

Yes, that’s it.
The very rare snarfblat.
By the way, turkey dinner was spectacular.

FLHTCUI.

 

[jmichelin84]

I believe it's a sewing machine tool, an old one

 

[ReverendX]

Ah yes.. one of those.. very handy to have.

 

[trevj]

I believe it's a sewing machine tool, an old one

Yeah, I could see that as a tool used by the fat-fingered, while running thread in to a sewing machine's works.

Not like any watch or clock tool I have ever seen, and I have seen more than most.

Take it to a sewing machine repair shop and see what they say. They will probably be able to tell you which make it was sold for.