With this bivvy sack, I turned a synthetic filled…

Rating: rated 4 of 5 stars
Price Paid: $26.50

With this bivvy sack, I turned a synthetic filled Wenzel mummy bag, rated around 30 degrees F into a really cozy mountain sleeping bag.

I slept inside this combination in a winter expedition at around 5800 feet in last December. The temp was 17 degrees outside the tent and no part of my body was cold during any of the two consecutive nights.

I also used the bivvy without additional sleeping bag in last summer, it had again done the trick, although I awoke towards the moning  shuddering a little because I was somehow half way out of the bag. Stitching around the velcro should be sturdier, though.

All in all, I recommend this bivvy to any hiker, backpacker, biker, etc.

Here's my review of Adventure Medicals' Thermo-Lite…

Rating: rated 5 of 5 stars

Here's my review of Adventure Medicals' Thermo-Lite Bivy:



Arson, you give the best reviews. Thanks for helping this cash-strapped guy get the most bang for his buck!

6 years ago

Turns a light summer bag into an impromptu 'colder…

Rating: rated 4 of 5 stars
Source: bought it new
Price Paid: $25


Turns a light summer bag into an impromptu 'colder weather' bag. Very compact, light weight and easy to use. Durable, and it's NOT a mummy style for us larger guys/gals.


  • Seemingly very durable.
  • Compact and light weight.
  • Will fit over most full size bags.
  • Water/weather resistant.
  • Opens at feet for ventilation.


  • Velcro tabs could be sturdier/closer together..
  • Used as a stand alone, condensation can be a factor.

On a recent summer outing with my Son, I made an egregious rookie mistake when packing and did not account for a "cold snap" that was moving thru the area. While low temps had been in the low/mid 60's F for awhile, on our trip they dipped down into the high 30's and low 40's for several nights. I had only brought my Coleman light summer bag (generously rated at 50 degrees), no jacket and no other blankets. Mistake..... huge mistake.

After getting virtually no sleep the first night (low 40's), grumpy and cold I remembered that I had an SOL Thermal Bivvy in my trunk (bought in 2016) for emergencies and my demeanor improved greatly. I put my Coleman bag inside the SOL Thermal Bivvy and the remainder of my outing was toasty and warm, even with temps. dropping into the high 30's.

My Son moved into my Alps Mountaineering Chaos 3 man tent from his hammock to share body heat (which helped), but I'm convinced the Thermal Bivvy added at least 20 degrees to my Coleman bag. With two of us in there, condensation became an issue, but was still warm the remaining 3 nights.

I'm a fairly large person (6'2", 230) and very much appreciated the 'roominess' of not having a mummy style bag, but had an issue with the Velcro tabs coming apart several times in the night. At the end of our trip, it was very easy to re-pack the Bivvy and put it back in it's sack.

I made a stupid rookie mistake despite my years of camping experience, but my SOL Thermal Bivvy saved the trip from being miserable. I'm gonna get another one (SOL Bivvy) and make it an integral part of my gear for EVERY outdoor excursion I go on.

Get one... toss it in your trunk/glove box... cause you never know.....


Bought it in 2016 for emergencies. Tossed it in my trunk and have used it once for 3 days as an augmentation to my Coleman summer bag. It saved an outing...

I would agree with Arson's very thorough review.

Rating: rated 4 of 5 stars
Price Paid: $26.94

I would agree with Arson's very thorough review. I defer to his review and would recommend this product. It does work.

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