The ThinLight pad is not designed for padding, but for insulation. It provides much better insulation for the bottom of your body than the equivalent weight of down when you are lying on it.
Made of Evazote® foam, these pads are made with a unique high pressure nitrogen gas solution process. High quality extrusions and cross-linking of solid polymeric sheets are impregnated with pure nitrogen gas at elevated temperature and extremely high pressure. Then the impregnated solid sheets are expanded in a huge low pressure autoclave. This process results in an extremely regular and uniform cell structure in the foam.
What this means to you is the foam is amazingly light and strong for its density. The pads are tough, flexible and resilient, and exhibit good UV stability. As a closed-cell foam, they will not absorb water.
The 3/8" thickness can be rolled, either inside the pack, or on top, or cut down to 30 or 40 inches, can be folded into the back of a Gossamer Gear G4, G5 or Mariposa, providing a super-minimalist pad.