ECN Forum Forums General Topics of the Trade General Discussion Area Gutter box for NM installs.

What is the point to having a gutter box such as this one in this thread:
https://www.electrical-contractor.net/ubb/Forum4/HTML/000433.html

for? I've seen them on commercial applications, but not on residential. Does the Romex run all the way through the gutter or does it get spliced in there?

Thanks.