1961 Models
There is a wide range of variants for the "1961 Models". We know of seven variants, plus a sub-variant to date; these variants are divided into five categories of knife, denoted by 1 to 5 and six types of “Waffenkontrolle” control stamps (or lack of a stamp) denoted by A to F.
Now the blade has a vintage stamp indicating the last two digits of the year (e.g. 63 for 1963).
PDF document, a copy of the plan for the Model 1961 soldier’ knife