Sand channel, PSP, Marsden matting

[Tony Smith]

Originally Posted by sapper740

During the war the United States made 2,000,000 tons of the stuff..... One will still see lots of PSP to this day as the high Manganese content in the steel alloy has helped preserve the planking.

Any idea how many producer's made the stuff, and if it was only Wartime production? I'd imagine there'd be sufficient war surplus to get through the post-war years, or was there? The rust resistance is true enough, the lengths I have all clearly show the manufacturer's name, but no date:

[David DeWeese]

Hi,
Dug out a couple of different examples of PSP from my junkpile today to see if they had manufacturer's marks also. The short wide one has no markings, but the long one does. Has a government contract number, so I guess it is probably post-war. I always thought they had discontinued making the ones with the holes after jet aircraft were in use.
Thanks, David