Smooth inside, corrugated outside? I made a long run using those. I think that the yellow markings are placed horizontally which orients the little holes in the corrugations to the vertical, probably to retard floatation. Don't forget the gaskets and lubricant. I joined them using two small-link chains with end hooks and a fence post puller. Very easy job.
I remember that offshore food, Beaux. I also remember some girl writing a motivational story about a guy who worked his way up from tool pusher to roustabout. Very funny. Not all writers do their research.
Keep 'er turning to the right!
