All About Pocket Knives

In cleaning out my parents home I came across several "vintage" pocket knives that I would like information on. This one is marked Klein Tools Chicago USA. and is in pretty nice shape. I suspected 1960's or 70's vintage maybe based on what was with it but based on some information posted here it looks like the "S" means 1981? Not sure what "S-3" means, maybe the pattern? Mainly just curious about the age and history of it. I gather from searches that these may have been made by other knife companies (Utica and others), anyway to tell who made this one? I will attempt to attach pictures. Is this the correct forum or should I use one of the others? Thanks.

Welcome to AAPK!
I was not familiar with the date code on these, but from looking it up here viewtopic.php?p=1087532&hilit=Klein+s+3#p1087532
I believe that your knife might have been made in 1981. From the look of the knife I am guessing that it was made by Camillus, but that is only a guess.
There are a ton of these out there so it has no real collectors value (I would guess $20), but I
am sure that it is priceless to you because of who owned it.
I would recommend putting a drop of oil down in the pivot, then wipe the blade with some light oil to prevent rusting.
Then occasionally carrying and using that good, sturdy knife!

I believe it Chicago cutlery

I was an industrial maintenance electrician for 21 years and had 3 or 4 of those Kline electricians knives a good work knife , use it and remember your parents and welcome to AAPK

Thank you for the information.