SOL Thermal Bivvy
Here's my review of Adventure Medicals' Thermo-Lite Bivy:
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.
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