The Forty Below® Bottle Boot™ 32oz/1 Liter size is the easy to use and effective insulating bottle cover that helps slow down the water from freezing quickly, especially in extreme cold environments.

It fits perfectly on both the Nalgene 32oz. size water bottles, and the 40 Below Cold Weather 1.0 Liter Water Bottle. Our 6 sizes of bottle covers have been used on the world’s coldest and highest places, since the 1970’s!

Please see below for additional information and specifications.

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The Forty Below® Bottle Boot™ is the easy to use and effective insulating bottle cover that help slow down the water from freezing quickly, especially in extreme cold environments.

This size fits the both the Nalgene 32oz. bottles, the  1 Liter 40 Below Cold Weather 1.0 Liter Water Bottle, and many others.

We have been making Bottle Boots™ now for over 40 years! They have been used and trusted and on just about every type of outdoor trip, from winter day hikes to extreme cold and high altitude expeditions worldwide! This very insulating water bottle cover, that is specifically designed to significantly slow down the freezing process, and easy hold onto and open and close with gloves or mittens on. The low profile, non bulky design takes up less room in your pack and less bulk when on a backpack hip-belt.

Forty Below 1 Liter Bottle Boot is the perfect Nalgene bottle koozie cover, fitting the several 32 oz. bottle models, and also the 1 liter German cold weather bottles, plus 32 oz. sport drink bottles like Gatoraide and Powerade. They also help keep fluids cool in hot weather.

Our unique design enables the user to easily open and hold onto with mittens or gloves, with easy access to the bottle, and no zippers to break or freeze.

Key Features

  • Fits most 1 Liter/32oz. quart size water bottles, such as Nalgene, German made Cold Weather bottle (Hunersdorf/KJS), Gatorade, Powerade, and others.
  • Easy to use with mittens or gloves
  • Helps keep liquids from freezing in cold conditions
  • Helps keep liquids cool in warm conditions too!
    Low Profile Design
  • Thick 6.5mm Closed Cell Neoprene foam insulation completely around the bottle
  • Does not absorb water
  • No zippers to break or freeze
  • Webbing belt loop
  • Velcro front closure with Grab-Tab
  • Easy to hold onto with gloves or mittens on
Get some Forty Below® Bottle Boots™ and see how this outstanding product can help you stay better hydrated and more comfortable in the outdoors!

To find out more about our complete line of insulated bottle covers, as well as more information about helping to keep liquids in extreme places, please see our All About Bottle Covers Section.

See it in Action

Product Specs

  • Insulation: 1/4″ (6.5mm) thick stretchy nylon covered closed cell foam (wetsuit type material). Same thickness completely around the bottle.
  • Size: Fits most 1 Liter/Quart size water bottles, such as Nalgene 32 oz. wide and narrow mouth, Hunersdorf 1000ml, Gatoraide 32 oz., etc.
  • Fits: Bottles up to 3 3/4 inches in diameter and 8 1/2 inches tall. Stretchy material so it can flex with different shapes of bottles.
  • Colors: Black, Blue, Red, Yellow, Pink, Green, Purple.
  • Weight: 3.7 oz (104g)
  • Handmade in China

The Bottle Boot™ name is a declared and used Trademark of Forty Below Ltd and is an original product and name that we invented, designed, manufacture, sell, and has been used around the world by us since 1980. Any use of the name: “Bottle Boot”, “Bottle Boots”, the design of the product, or trade dress is prohibited.

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