FITS Wader &ndash; OTC: Over the Calf High Performance Wool Sock WADER: This over-the-calf sock comforts your entire lower leg with super-soft Merino Wool and keeps you just warm enough in those ice-cold waters. Best of all  pull them up once and theyll stay up all day. From brook to blind, this sock does it all TYPE: The 100% Merino Wool interior provides excellent moisture control and comfort while the Nylon exterior provides maximum durability and abrasion resistance. A Dynamic Toe Cup prevents bunching in a critical area of the foot. FIT: Engineered using FITSs innovative, full contact fit technology and dynamic toe cup to contour to the shape of your foot. The patented heel lock provides heel security that limits the chances of a blister when combined with a properly fit boot. CUSHION: Designed with cushioning surrounding your entire foot, ankle, and calf, the Wader provides excellent thermal insulation and moisture control in any environment. A double-welted top so the sock always stays up prevents binding or slippage. FABRIC: Merino wool feels great against your skin, is naturally anti-microbial, and flame resistant. Innovative knitting construction moves the seam back from the sensitive toe area while nylon reinforcement on the outside of the sock increases durability.