Machine Washable Heat Holders Lite – This new innovation of Heat Holders solves the ‘to thick’ element to the original Heat Holders. These Thermal Winter Socks are thin enough to fit into your casual shoes, but thick enough to still allow Heat Holders’ heat insulation techniques to work. If your struggling to get your thick Original Heat Holders into your boots or shoes then here is your answer! Heat Holders Loops – Innovative knitting tehnology produces our unique, extra long looped cushion pile to hold in more warm air, increasing the TOG rating. Heat Holders Brushing – Finally, our expert brushing process maximises the amount of warm air held inside each sock for total warmth and all day comfort. Heat Holders Lite Tog rating – These socks are scientifically tested to be 5x Warmer than a basic cotton sock, with a tog rating of 1.6 Heat Holders Yarn – Our Specially developed thermal yarn provides high performance insulation against cold with superior moisture breathing abilities.