All About Pocket Knives

I don't usually mess with these kind of knives but was at a knife show today and a guy pulled it out of a box with other knives that had belonged to his dad who had recently passed away. Can anybody tell me what the age or value is for this knife. The stamp on the tang says USA

These knives were mass produced in the 1970's and current, they are worth $15-20 and some of the older Novilty
Knives are quite collectable.