All About Pocket Knives

hello to all, im new here and i have a question about a camillus knife.it was my grandpas he died in the late 70s.it is a small pen knife with yellow handles,has 2 blades and has 22 stamped on the larger of the two blades. i was wondering how old it is and possible value other than sentimental.any help will be appriciated thanks in advance GD

The #22 was called a "Pony Jack."
2-13/16" closed.
Swedge ground clip and a pen blade.
Approx dates, circa the 1950s to about the mid 1980s.
They had yellow plastic handles.

The value would depend on the condition; about $10 in Very Good condition and maybe as much as $25 in mint condition.

Hope this helps,
Dale