Has anyone regularly done 48 hour shifts? How realistic is this option?

Curious as to what you folks think about this option. Saw it recently on a job listing and was wondering how realistic is it? I mean how the hell do you pull 48 non stop? Assuming this is the norm and no sleep is going to happen. I cannot imagine personally, let alone legally speaking.

Well I misread..................its not 48 hrs in a row as I misread

https://gaswork.com/post/538750