Women's Jennifer LITE™ Heart Crew SocksAdvanced thermal yarn Sensationally soft More than 4X warmer than a basic cotton sock! Non binding Heat Holders LITE thermal socks have been designed to provide our famous thermal protection and comfort in a medium thick profile, ideal for wearing in casual shoes and boots! Compared to our ORIGINAL, maximum loop length thermal socks with 2. 34 Tog rating (Thermal Overall Grade), Heat Holders LITE thermal socks have a medium loop length with 1. 60 Tog