Originally Posted by Niko


I searched the Southwire PDF file on THHN/THWN and the white book but could not find anyhting specific to the nylon jacket.

or the nylon covering is strictly for easy pulling?


Sometimes THHN does get scratched if you are not careful. I would not scrap the pull for this minor problem, unless it was bad. That rarely happens.
I guess the nylon thermoplastic covering serves both purposes.