Description: To determine your size, measure the circumference of the fullest part of your calf. ; Running in regular, non-run specific socks can progressively ruin your day not to mention your workout. Build stamina, boost energy and recovery more quickly with the help of these women's Running Progressive Compression socks from CEP. ; Features a patented 12-18mmHg compression sock to maximize muscle oxygenation and boost energy with unparalleled compression technology for all-day benefits. ; Great for: Pre-Exercise - Activates muscles while reducing the risk of injury. During Exercise - Optimizes performance and stabilization while reducing muscle strain. Post-Exercise - Quicker and shorter recovery phase. ; Achilles heel support protects and prevents irritable tendons. ; Ventilation channels create a pleasant foot climate. ; Padded sole helps prevent blisters. ; Anatomically-shaped left and right inline seams adjusts to the anatomy of the foot for a perfect fit thanks to medi's three-dimensional manufacturing process. ; Used by professional triathletes around the world. ; CellTex Fiber finishing facilitates the biological activation of skin cells and provides a comfortable, skin sympathetic and climate-regulating wear. ; Protects the shin against shin splints and impact stress. ; iPS (Integrated Power System) - A defined compression with scientifically patented pressure profile improves blood circulation and enhances performance. ; Consists of 85% polyamide, 15% spandex. ; Wash in cold water. Tumble dry in low heat. ; Product measurements were taken using size IV (15. 5-17. 5 Calf). Please note that measurements may vary by size.