car sun shade?

[Bearpaw]

I haven't used one personally, but when I hike the Colorado Trail 3 years ago, Roni from Israel grabbed one at the Walmart in Buena Vista. He had been sleeping cold with this pad (having come from the AT in Virginia to Denver and south). He bragged joyfully about how much more warmth it gave him. Of course, Roni took pride in being notoriously cheap also, so the fact that he got it for about $6 didn't hurt either.

[stretch]

I have used the mylar/bubble wrap truck shade from walmart with good result. Used with a 30* cheap walmart bag as a pea pod I was warm at 35*F.
I think it bunched up pretty bad on me, but since its not a very still material it wasn't that uncomfortable.

[Peter_pan]

I used one in the days before UQs.... generally worked to abot 55*.... with sweaty back I might add, for me at least laying on it in the hammock, above 60*...

Pan

[te-wa]

i compared these directly to ccf for r-value and weight
i found, in quite a non-scientific way that the reflector and 1/4 ccf have nearly the same warmth and worked for me to a minimum of 45°, yet the reflector came in about 35% more weight than the ccf.
im a self-diagnosed "warm" sleeper and wouldnt use the stuff below 50, unless in an unforseen weather incident.

[Don Sanders]

Just made one. Sewed a fleece blanket to one side and it worked great on 48 to 58 degree nights without any blankets or bag. The body heat reflection is significant. The only problem is my elbows have no protection and at 6' 2" & 225 lbs it could be a little longer. Weighs 29 ozs. My wife says I should make a short piece just long enough to cover my shoulders & elbows and velcrow that piece crosswise to the longer section. Make sure you get the truck size.