TOG means Thermal Overall Grade. It is a scientific test that measures the thermal (heat retaining) capacity of fabric. Heat Holders® original thermal socks, when tested using this standard, rate TOG 2.34*. This is 7x warmer than cotton socks and almost 3x warmer than ordinary thermal socks! We test socks from most major brands that we can get our hands on and it is safe to say that Heat Holders® thermal socks are almost 40% warmer than the warmest thermal sock we have ever tested, which was a heavy sock with 80% plus wool!

This is why we claim that Heat Holders® are the warmest thermal socks™!

*Heat Holders® LITE socks rated 1.6 Tog. See the difference in warmth.