[Dick Herman]

Once again from the Gortz & Sturgess encyclopedia K date reference.

The principle way to identify the different K date Sub-Variations is the S style inspection markings on the small parts.

1st Sub-Variation has Fraktur S (Funny S) on sn less than 17xx.
2nd Sub-Variation has Fraktur S and Roman S between sn 17xx and 56xx.
3rd Sub-Variation had Roman S between sn 56xx and 91xx.
4th Sub-Variation has no small part S markings above 91xx

Also the 1st and 2nd Sub-Variations also utilize a Fraktur S (Funny S) on the toggle link S/42. Subsequent K dates have a Roman S on the toggle link S/42.

I just realized my 2nd sub-variation is numbered beyond the published serial number range, sn 5970. It has all the characteristics of a 2nd variation, it could be transitional or just one the authors had no information on.