The "What Is This?" game

[Janx101]

Solar heating box. .. for...... really small pool? Or fish pond maybe to circulate warming water so fish don't become ice blocks?

[Elmojo]

It appears to be a solar heater like Janx said, but for air, not water.
Can't imagine what for....

[axexandru]

preheater for an air exchanger?

[Big Rich]

It appears to be a solar heater like Janx said, but for air, not water.
Can't imagine what for....

Close enough for me! It's a solar heater that I hang in a window during the winter months. If you look around online for a "soda can solar heater", it's the same concept. But I found out soda cans are next to impossible to work with.

Good get Mojo!

[Elmojo]

Wow, pretty cool! Or warm, actually. 
Ok, gotta find something....
Alrighty, give this a gander.
I suspect one of you old coots will recognize this right away. (that was a hint, BTW)
For size reference, the electroscribed lettering is roughly 1/4" tall

[attachment deleted by admin]

[ShowBizWolf]

I have NO clue... anybody out there? 

[Elmojo]

Oh goody, maybe I picked a tough one! 

[Big Rich]

Bean counter?

[Elmojo]

lol no.

[Big Rich]

Wouldn't be part of an old sewing machine, would it?

[Elmojo]

Negative.
Here's a hint: It's a tool, but is not part of anything that's used to make or create anything else.
(For example, a sewing machine is used to make stitched items)

[mennobike]

  I've got nothing

[Big Rich]

Is it for audio equipment, like a record player?

[Elmojo]

Nope.
It's a tool, but it's not used to make, adjust, modify or repair any other thing.

[Big Rich]

Almost looks like an old profilometer....

Is it used to diagnose or measure something?

[Janx101]

I don't know why but I think it's for locks and keys somehow

[Elmojo]

Nope, not a profilometer (or related to locks Janx), but Rich in on the right track...
It does indeed measure something.

[Janx101]

Measures the angle of the dangle!?

[ShowBizWolf]

I just LOLed here at work hahaha 

[Watcher]

Is it for measuring tension?