I received a small sample of 8oz poly with about 50-60 threads/inch. I tested it by ironing and it shrinks about 10% (and even more if you get it too hot). I tried painting it with an oil based paint and it seems to nicely take the paint. I put a second coat on and believe that would seal it. But, as this is new to me, I have nothing to compare it to.. Anyway, I won't be working on my kayak until this summer when I go to Washington, so I thought doing some research might turn up something. But, now as it turns out, the supplier has run out of the material and is no longer offering it for sale.