I am trying to understand the difference between the AMK Emergency Bivvy and the AMK Thermo Lite Emergency Bivvy. Does anyone own both or either.

In case you are unsure here are links to each

http://www.redflarekits.com/pc/1038/s/Heatsheets+BIVVY+SACK%2C+Emergency+Survival+by+AMK

http://www.redflarekits.com/pc/1034/s/Thermo-lite++emergency+bivvy+sack-+1+person

Is it just that one is more durable than the other or is there some other difference. Which is better.

You may want to do a search on the forum for bivvy . Doug also did a review on the main site.

It's been brought up before, but I don't think anyone has done a review... Anyone have any comparisions of the MPI Outdoors Extreme Bag?

Thanks,

-john

It is all a matter of the classic sleeping bag tradeoff: more weight and bulk for more warmth.

The HeatSheet bivy is the smaller & lighter model. But the ThermoLite has a bit more insulation value (though slight). You pay for that with more weight & bulk.

This is the same deal with the MPI bag. It actually provides dead-air space insulation, but (once again) at a higher premium for weight and bulk. Here is a link to the manufacturer of the MPI bag. It is very interesting technology.

As always, it boils down to your intended use. If we're talking about a car kit or something where you aren't carrying the weight, the MPI bag would be awesome. If you are on foot, the lower weight/bulk products might be a reasonable compromise, especially when combined with gear you'd have on hand in addition to some creative bushcraft.

Tom....
Check out the thread below.

Emergency bivvy sack

Hope this helps.

Smitty

Thanks Smitty that was just what I was looking for. I don't know why I did see it originally. But thanks

Tom

As I'm about to buy such a bivvy, I asked some questions to Aeromedix.
Here is the answer :
"The dimension on the Thermo-Lite Bivvy Sack when stored are approx. 6"x3.5"

The difference between the Thermo Lite Bivvy and Heatsheet Bivvy is
mainly the material. The Thermo Lite Bivvy is a much more heavy duty
item for more serious conditions. "

As for threads about bivvies, search for "bivvy" and for "bivy" !!!

The improved ThermoLite 2 version of the AMK bivy is starting to show up, I saw them at REI this afternoon ($33). It advertises 30% stronger than the first version. I may spring for one eventuallhy to compare to the more compact Heatsheet bivy ($11.79 in quantity from RedFlare), but they seem to use the same material so I'm not sure about the cost/benefit. Last November I slept out in the backyard during 40 degree wet weather in the Heatsheet (blue foam pad, typical hiking clothes, hat and gloves) and passed a quite comfy night rain sheltered beneath a beautiful cedar, since lost to the December windstorm. The Heatsheet held up and is refolded and ready for use in my dayhike gear. I bought a bunch of these when they came out and spread them across kits, cars and relatives. They're small enough to carry extras on Scout outings as well for the inevitable cold Tenderfoot...

ThermoLite 2 description at http://www.adventuremedicalkits.com/kit_...kitNO=0140-0223

I went ahead and bought a couple of AMK emergency bivvys and a packet of three 4.5 x 7 inch Aloksak-bags, from Aeromedix. Man, those bivvys are small folded.
I put an AA battery in the picture for size comparison.