I'd saunter down to the paint department and buy a roll of Gorilla duct tape before I bought something like that. It's like a solution looking for a problem.
Some facilities have specs that require all conduit runs to be capped when not working on them. Maybe at one time water leaked into equipment thru an open conduit
A standard EMT setscrew fitting wouldn't help that issue. Those connectors aren't even intended to be water tight.