Calf Boots by UGG. The Classic Tall Ugg boots we all know and love has been upgraded with the addition of pre-treated against stains & moisture uppers. The Treadlite outsole providing you with even more cushioning and traction is another new feature making this boot the perfect companion this winter! Twin-face sheepskin & suede mixed upper. Pre-treated against stains & moisture. UggPure wool insole. Treadlite by Ugg outsole. Please be aware that our genuine UGG boots are only available in half sizes. If you are normally a size 6 please order a size 6.5 as this is the equivalent size.