For serious cold, break out the big guns. Thorogood® Mountain Ridge Hunting Boots are built for the most extreme of conditions, delivering rock-solid waterproof/breathable construction and 2,440-gram ThinsulateTM Platinum Insulation. Thinsulate Platinum Insulation goes beyond standard Thinsulate, offering even better warmth-to-weight ratio—and it's effective even when wet. This is the highest insulation value of any boot we offer, and it's the best insulation on the market. If you want the warmest, you've found the warmest.