I have seen a few times on ebay what is called in French a Butterfly Straight Razor (coupe choux papillon). Basically, these are straight razors with two blades in a single unit of symmetrical scales. My attempts to find information on these razors ended up without any results (probably also because I don’t know what they are called in English, and because TTO DE razors in French are also called “rasoir papillon”.

Does anyone here have any info on these, and what they are designed for? This is what they look like.