A unique micro fiber developed by 3M, Thinsulate™ has more surface area to trap warm air, insulating better than other high loft insulations, including down. It is less bulky for use in moderate cold conditions.
Thinsulate™ insulation works in footwear, including winter boots, because it doesn't bog boots down with weight and it absorbs less than 1 percent of its weight in water. This means it's not only one of the lightest synthetic insulations on the market, but it keeps feet warm even in damp conditions. The Kamik and Ranger boots on this page all feature Thinsulate™ insulation.