Fully waterproof boot with waterproof elastic and latexed seams. Upper is premium waterproof leather. Lined with Thinsulate insulation. Thermo urethane outsole resistant to hydrolysis and microbial attack. Polyurethane midsole for comfort. PORON® XRDTM in the heel strike zone to dissipate heel strike shock. Removable sheepskin footbed for warmth and comfort. Upper: Leather Half sizes increase width only, not the length of the boot. Blundstone boots and shoes are marked with Australian/United Kingdom sizing. For an accurate fit, please refer to the size guide below.