Here is one I picked up recently.

It's a 1943 knife in an Von Lengerke & Antoine sheath. Most of the fighters sold by VL&A were shipped from the shop without sheathes and fitted at the store.

The fighter Bo designed with Zackarias in late 1942 had a pronounced hump on the back of the blade. There was a short period of time in 1943 when the hump went away and the grinds seemed flatter. This is one of those knives.

The hilt and butt cap are very thin and the handle is smaller in diameter with more taper towards the butt.

Later in 1943 the hump came back into the pattern.

The three knives in the second photo were made within a one year period. There was a lot more variation in the grind, hilts, spacers and handles prior to later 1944