I just added this jewel to my fighter collection. My thanks to one of our fellow forumites.

It is an early chain link, Model #1 - 7".

Two things about this knife are worth pointing out.

First is the flap on the stone pouch. It has the rounded "lobe" shape like Clarence Moore sheaths. The assumption is that Bo sent a Moore sheath to Heiser as a pattern for their first orders.

The other is the flat grind of the blade and a much less prominent hump on the spine. I have an 8" knife that is very similar.

It's an mid 1943 knife...... and in great condition.