There is a brief section describing it here: http://www.equipped.org/shelter.htm

The product webpage is here: http://www.land-shark.com/

According to the site it is built out of a rugged 10 mil ripstop material with an aluminzed coating.

It does seem like a major improvement over cheap mylar bags. The one feature I'm not sure about is the tether and clip. While a great idea, I don't think I would trust that cheap plastic clip and drawstring to withstand the force of several people being pulled in different directions in rough seas. I'd much rather see somthing like para-cord and a metal clip. And you can't really unpack the bag to modify it, since that would defeat the convenient, compact vacuum sealing.