This is basically a somewhat more durable version of a single layer mylar blanket. This survival blanket is considerably more durable, tear resistent, and useful. At about 2/3 of a lb, it is heavier than a single layer mylar, but well worth the weight.
I use it as a ground sheet under the tent, as a picnic blanket, as a seat during hikes and as a rain tarp for shade. With so much multi-use flexibility, this is one of my must have backpacking items and has been for about a decade