Two-hole screw on a Kofod Larsen chair  

That is called a spanner head bolt. I have a set of IKL dining chairs for Selig which have this same bolt. While you can certainly buy a spanner head set with various distances between the points, it may not be worth the cost (and additional tool clutter) since you don't need those bits very often.

Two alternate options are:

1) thin needle-nose pliers, or

2) take two nails (or ends of a paper clip), tape to a coin to fit the distance between holes, and presto . . . instant spanner wrench.

. . . and for curiosity, could you post a photo of the whole chair?

Thanks cdsilva. Yea I figured it out and i think I have the tool for the job.

Attached is a photo of the chair. Needs a bunch of work but it's a beauty.

Nice; model 15-15.

That's it alright. One thing i am not totally sure about at this point is whether the wood is walnut or the walnut-stained beech that I have seen used for other IKL chairs for Selig. Any thoughts cdsilva?

Almost all of the Selig "walnut" chairs are stained beech. There are a few designs that used solid walnut.

The first photo you uploaded shows the top coating flaking away (some type of lacquer I think). So that usually indicates stained beech for the Selig pieces, unless someone did a DIY lacquer effort afterwards.

Figured as much. Thanks again cdsilva!

Hi there, I am having trouble unscrewIng the same type of screw disk with tiny holes from a Larsen chair. Can you tell me what you used? Do you know where I can buy replacement screws? Thanks