I've slept in one of these with a 2 season sleeping bag. They're truly amazing. After 3 hours I had to get out (it was minus 2) before my body boiled. Everything they say about them is true. But, condensation will be a problem, and everyone around you knows you're in one. In the dead of night, you may as well be breaking glass, it's that noisy. I would carry one as an emergency shelter only (mountaineering). It is the cheapest '4 season sleeping bag' on the market and will challenge the current minimum requirements for kit at events

Any idea how much these cost? I wondered if carrying one of these would fufil the kit requirement for an emergency bivvy bag?

�29.99 - advert on Polaris website
They more than fulfill requirements, so you can use lighter bivvy bags for this reason

Thanks Gary, I think I'll stick with my regular bag or possibly chance the Snugpak Softie 3 in the unlikely event the weather forecast is "balmy"

I'm going to try and get away with my Not So Snug Super Crunchy Puffy Crispy Packet 3 and fill it with sheep wool, grass and bird feathers. Ah Ray Mears, eat your heart out

Just trying to find out about the tin foil bivy bags that i saw for sale on the website before the spring race. does anyone know anything about them. I cant be bothered carrying the large goretex bag that i have!
cheers