Does a very good job keeping your liquids warm in the winter and cool in the summer - decently thick neoprene. Simple fold-over top and wide hook and loop closure is easy to use with gloves or mitts. Sufficiently compact that they fit easily many backpack bottle pockets. If you sleep out and hike in freezing weather, you have to answer the question of how to keep your drinking water from freezing. Forty Below's neoprene bottle boots are a great solution, unique in many ways. Most winter bottle… Full review
Forty Below 32 oz / 1 L water bottle parka / boot holds one Hunersdorf Expedition 1 L water bottle or one 32 oz / 1 L Nalgene water bottle. Forty Below Water Bottle Boots / ParkasThis is the yellow 1 L / 32 oz size No zippers—can open with mittens on. But you need to ensure the seams are closed together tightly wen you put the water bottle back in, with the lid on the bottom because the ice forms on the top. With the upside down bottle, any ice that forms is on the bottom not frozen under the… Full review
Forty Below makes climbing equipment for extreme conditions.