I figure it's time we had a thread to specifically address the use of fittings that accomplish, as best I can tell, things you're not allowed to do.

Now, it's possible that my understanding of the NEC is flawed. After all, all of the fittings I intend to bring up are UL listed- and UL, as a matter of policy, will NOT list something for which there is no code-compliant use.

Today's fitting is a new one, proudly introduced by Bridgeport Fittings. The fitting is intended to allow for the direct connection of MC to EMT. Look at it here: http://www.bptfittings.com/Home/ProductDetail?id=00781747944562

Now, the existence of this fitting brings up any number of tangents ... but I'd like to limit our discussion to one: namely, is there EVER a circumstance where you can use this fitting?

Some might say "sure- I can eliminate a box and just extend the MC wires back into the pipe, as far as I need to go, until I get to a box I really need."

The problem is- and feel free to correct me here- I think the NEC requires the wires to be marked with insulation type, etc. .... and NO ONE makes MC with marked wires.

What do you think?