The webbing from NRS (the kayaking place) is very strong. It has an inner weave that you can't see. I've used them for many years and never had one fail. I've also bought cheaper look-a-likes with bad results.
Miguel
Printable View
It sounds similar to tubular climbing webbing, which is definitely heavier than, say, Ed's 1" poly stuff.
http://www.nrsweb.com/shop/assets/prod_img/1450F.JPG
from the website: Custom make your own straps. 1500 lb. tensile strength polypropylene webbing.
Oh ok, cool...not tubular, but it does look beefier than Ed's webbing.