Whats it

[chips]

1/2" drive marked VG-1 with some kind of circle symbol.

[Bill Houghton]

Given the thickness of the fingers, I'm inclined to think that it's for removing things that are threaded into a component, and have slots cut at the edges.  For instance, some fuel tank float/sender are built that way.  Or drum nuts.  Or something similar.

I think there may be plumbing components that are similar, too.

[bill300d]

Adjustable valve lapping socket. The two tabs on the right fit into a slot or in some cases 2 holes on the face of the valve to turn the valve to lap the sealing surfaces.

[turnnut]

my thoughts were the same as Bill300d;

 I have Walden's tool co.'s  VG2   and VG3  valve lappers,  one is short  and stubby and the other is long handled.

 the end that fits into the top of the valve looks like those tabs.

 somewhere I have a Mossberg,  I think that one is adjustable, it is also a long handled brace style lapper.

[bill300d]

Heres my New Britain None Better brand lapping socket.

[bill300d]

When I enlarge your photo I can see marking on the last pic. Is that a circle with an H inside I would guess Hinesdale

[turnnut]

that New Britain would work good with a speed wrench, you could get a decent back and forth rhythm.

never seen that one before, thanks for sharing.