Found this in an old cigar box, but don't know what it was used for.

This tool is a combination   feeler gauge and wrench for setting the points in an Eisemann magneto.   I have a set,  over half of the wrenches have built in feeler gauges.  Neat little tool,  nice to see something survive 75 years plus.

Ebay sellers marketing it as a "Vintage Motorcycle Ignition Contact Wrench".  I tend to agree with John in that it is a wrench for adjustments to a Eisemann magneto.......not sure on the applications of the specific magneto, if any.  It could be for light aircraft as far as I'm concerned.

The one on ebay has "spark plug gap" on one of the feelers, does yours have that too?

In many (possibly most but I am just throwing that out there ) cases these little ignition wrenches were part of earlier autos original dealer packet ( not too be confused with toolkit ) if the auto ( assuming this little guy was intended for auto ) was equipped with a large name ignition electrical system.

I (think I/used to) have a similar wrench that came with a Jawa (CZ) Czech motorcycle a group of us owned 40 years ago.  If I still have it, it's the only remaining piece of the motorcycle I still have.  Neat bike; square section tubing in the frame, other odd design features.  Took ten minutes to start it, ran like a (very noisy two-stroke) clock after that.  It had been modified for dirt use, and gave you the feeling that, if you fell off, it would come back and pick you up.

It came with two feeler gauges, one, I believe, for the points gap, one for plugs.

I agree with John K and 1930. It is for setting up an Eiseman Magneto. I don't know if they were shipped with the mag or in the garage service kit for magnetos.

I forgot to add that often times when there are holes present within the tool such as yours it may be an indicator that the wrench was special equipment for an auto that carried ( for instance ) other Eisman accessories such as ( for instance ) a horn or gauges ect.

The small hole cut-outs would have been used to adjust or dismantle these other items present on the vehicle.

Just something else to consider for what its worth

they came with caterpillar tool kit on their early gas tractors.