HIGH-PERFORMANCE SOCKS FOR THE ACTIVE DAYS - THE SIMMS GUIDE THERMAL OTC SOCK. These socks are spun from a perfect blend of fibers to provide you with all the features you need for a comfortable, productive day. The Simms Guide Thermal OTC Sock features premium merino wool for advanced moisture management and nylon, polyester, and lycra for stretch and comfort. The over-the-calf construction keeps you warm when it matters. Women-specific fit High-loft, over-the-calf design for maximum warmth Right AngleA(R) arch support Premium Merino wool for moisture management & odor preventionTECH SPECS Fabric: 75% Merino wool / 20% nylon / 3% polyester / 2% LycraA(R) Weight: 6 oz. / pair