These blankets literally saved my life.
I now have 50 of them. I ordered them here - although it doesn't matter where you order them:
Edit (story): My wife and I did some wilderness hiking in March and decided to go ultralight. Long story short, we were several miles out when a system moved in and the temperature DROPPED. We were using hammocks, no tent this time. You know how some sleeping bags are rated to 20 degrees and you think you've gotten a good deal on them? Well, these were more like 40 degree bags. This was an area where cliffs were abundant, so hiking out at night wasn't really a safe option. We went from wearing short to absolutely freezing, the temp dropped into the teens and it began snowing. We were in trouble. We wrapped up in our emergency blankets, got into our sleeping bags, and wrapped up in a tarp. The condensation of our breath was my only complaint about them, they'll get you wet as you breathe under them in cold conditions.
They kept us alive. That's the gist of it. We hiked out at first light after not sleeping at all.
Man, breakfast the next morning was amazing, as was the heat of our vehicle.
We have since invested in good, actual zero degree bags.
No, the ref is the referrer, what channel you came through. Like, user-specified search, sponsored listing, similar products, products you might like, etc. The referral link id field is "tag" and the value usually ends in "-20" (sometimes "-21", IIRC). My referral link for that item looks like this: