Utilizing proprietary 100% waterproof, breathable and windproof StretchDry technology the SealSkinz Mid Weight Knee Length Waterproof Sock sock is perfect for a multitude of activities and conditions. The SealSkinz Mid Weight Knee Length Waterproof Sock will keep your feet dry and comfortable no matter the conditions. The SealSkinz Mid Weight Knee Length Waterproof Sock utlizes merino wool for the inner liner to ensure moisture and comfort control. Elasticated ankle and insteps offer support and a secure fit. Not waterproof if water is able to get in through the top of the cuff.