Thanks for the link.
As for triplex not being UL listed, I think the man just might be right based on my limited experience. Back in the day, I needed some for an overhead run to a barn. Checked with a friend who worked at local power co. service center. Told me the power co. could not sell it to me because they did not get the UL listing. However HE could buy it and he did and sold it to me. What's the difference???????????????
Some years later needed some more and bought it from my regular electrical wholesaler no questions asked. Don't know don't care if it was UL approved or not. GO FIGURE.
Leonard BSEE NCSU '65