Those are Salesman Knives. The idea is that a travelling salesman would have a knife with every doodad the company offered on it, and people would pick and choose what they liked best and the salesman would send the company a letter with the order and move on to the next town. A while later the person's knife would arrive in the mail.
At least, that is the story I have heard. I can't say with 100% certainty that it is accurate, but that is what I'd heard.