
My beanie I used 30 days consecutively in the Eastern Sierra's with temps as low as 22°. My Trapper Hat I use on all snow backpacking trips. Temperatures varying from 50° - 0°. What makes these hats and this technology work so well for me is that I never over heat, but it really does keep the heat in when I am being active on the trail and not just sitting at camp.
About Omni-Heat:
The Omni-Heat® thermal reflective interior adds more warmth without adding bulk by using reflective fabrication to capturing and retaining your body heat.
The little kid in me loves the look and styling of both these hats. The adult in me appreciates the warmth factor in the technology. Its a win win for both of me. (smiling)