Mystery Collet Holder

[NikolaiBorjeski]

I recently purchased a Fray milling machine that came with some misc tooling, along with it was a nice German made (maybe Swiss?) collet holder that I'd really like to get more collets for, but I'm having a very hard time identifying them, they're not ER or TG collets, maybe DNA collets? The only markings on the holder are Stieber & Nebelmeier, a SN number, and a 1/2 denoting the drawbar thread, all of which were very faint.

 

[markba633csi]

They could be DNA- here is a page describing the various sizes:

 

[Ecosta777]

Looks like it might be an SK?

 

[NikolaiBorjeski]

Looks like it might be an SK?

You might be right, I'm going to order an SK25 collet and compare them.

 

[NikolaiBorjeski]

Just checked with a caliper and it seems that SK25 is close but not the same, the diameter is too large.