Removable, unique multi-layer foam inner boot system adds superior warmth, slim design, and is much lighter weight than more traditional felt designs. * ICEPAW anti-slip outsole for extra grip on slippery surfaces * Integrated Arctic-flex Rubber base that maintains flex in the coldest conditions * Rated to -94 degrees Fahrenheit but not uncomfortable in warmer conditions * D-ring lace system for no hassle/easy fit adjustment