In my mini survival kit at the bottom of my backpack I keep a letherman, ducktape, some food and a space blanket. It is one of the lightest things you can carry that has the biggest impact on survival in the mountains. this one is way more durable than many versions, and like alpinejames said bellow it wont delam after a year of kicking around in your pack.

I got this to replace an old space blanket I had that kind of fell apart when I had to use it when I got caught in a rain storm. This one seems way more durable, compact, light, and totally worth the 3 dollars. I definitely recommend buying one and keeping it with you on hikes and campouts. You never know when you might need it. And it's bright orange. What could be better.

This blanket is very well thought-out. Compared to other blankets with similar purposes, this one is much less crinkly sounding, doesn't de-laminate into uselessness after storing it in my first aid kit for a year before unfolding (like others do, grrrr....), is quite fire-retardant (useful, as bivies and fires sometimes go together), and does what it claims, that is, reflect heat. It does it so well, in fact, that sitting next to a bivy fire I could feel warmth on my face and exposed arm areas, but not in the areas the blanket covered. Weird. The package claims it is re-usable and re-foldable which I agree with, but it never quite stuffs down as compactly as it began (it ends up being about 2x the size versus about 20x the size for other blankets). Well worth the extra $1.50 or whatever it ends up being vs the competition. Would be worth double, or even triple. Nice work, Adventure Medical.

Consider it an ultralight, cheap insurance policy. It's less than 3 oz and $4. It can save your life and it doesn't eat bread. Buy one and carry it.

It is what it is...and it's durable.