The common box cutter (American English translation) that I am familiar with is a standard single-edge razor blade slipped into a metal frame so that one corner of the blade is exposed. That is enclosed in a rectangular spring-steel "sheath" about 4" long that becomes both handle and sliding cover for the blade.
Hold the case/cover, knock the butt end on your thigh, and the blade is exposed. It is used to quickly open cases of goods in grocery stores.
The "Stanley knife" is a higher-priced variant.