The 20-30mmHg socks cannot cure your calf problem,but they can help reduce and alleviate pain,as well as help prevent calf injuries. Features: Comfortable & Flexible: The socks are made with 30% spandex and 70% chinlon material.Breathable fabric features maintain stability and provides moisture absorption. 20-30mmHg Socks: The socks have pressure from the ankle to upper thigh. The socks deliver 360-degree stretch for greater flexibility. Effective: Help to improve blood circulation,prevent the ankle,leg and foot swelling,reduce muscle cramping and prevent the risk of developing varicose veins,pulled and leg fatigue etc. Anti-slip: Anti-slip silicone points inside for upper thigh,provide good grip and prevent slipping down easily. Great For Daily Use: Suitable for most needs,like running,hiking,volleyball,basketball,cycling,baseball,yoga,workouts or any fitness activities.The calf sleeves are also perfect for everyday use especially for athlete,teacher,flight,receptionist,office worker,elderly etc. Specification: Color: Beige / Black (optional) Size: M / L / XL / XXL (optional) Material: 30% Spandex & 70% Chinlon Package weight: Approx. 109.4 - 130.7 g / 3.9 - 4.6 oz Package size: 23 * 15 * 2 cm / 9.1 * 5.9 * 0.8 in Package List: 1* Pair of Socks NOTE: 1. Please compare to the size chart and measure your circumference to get the best size for you. 2. The socks have strong pressure,please choose bigger size if you fits both of two size. 3. If you are initial to use or over 45 years old,please choose bigger size. 4. Please wash by hands and hang it outside to air dry.