What is a half-open knife like?

Usually, the tool has a half-open edge, 1/3 open edge, etc. , which means that a tool is allowed to be held by someone, and the distance from the tip of the tool is 1/2 or 1/3.

This kind of knife is usually a long knife with certain commemorative significance, and the social credibility of the knife holder is high.

My friend's father is an old revolutionary and war hero. He has a Longquan sword with 1/3 blade, which was specially approved by the public security bureau.