What kind of screen cover was this?

I was in line at Subway today and there was a guy ahead of me with an iPhone inside of a black silicon case. What caught my attention was that he removed what appeared to be a hard, clear plastic face protector that fit perfectly in place when he answered a call. He walked off with his food before I got a chance to ask him where he got it.

Does anyone know what I'm talking about and where I can get it? The only search engine results I get are those iPhone adhesive screen shields, and those aren't what I'm looking for.

Thanks. 🙂