Here are three 1.13.23 knives with the backpacker icons embossed and they are from three different time periods.
The number one knife got the short key chain ring and it got a different shade on the red scales. This is not possible to see on the picture or maybe just some. The scales are red.
These knives got the special flat Phillips tool and this has caused some problems to date. When Wenger first introduced this I do not know yet. The number 1 knife I have put to 1980 on the time frame.
The number 2 is almost the same with similar icon but longer key chain ring. Usually on my knives it seems the short key ring was used also later on but the long one was not used earlier on. It is uncertain
to use this for dating a knife, it only give a hint.
There are a few small differences so I have put it in 1984.
The number 3 knife got
more differences with a larger embossed icon and the locking flat screwdriver (1982-1984) + some more. I have put it in late 80s, maybe 1989.
All of the knives got the short can opener and old spring
The knives with embossed icons are fun to collect and many like them. They got a reasonable cost and variations in
them. I would expect that there are many more models out there than we know so far.