Features: The foot massage stimulate the acupoints of the feet to promote blood circulation and keep warm. Made of high-strength materials and exquisite sewing, it is soft and comfortable. Suitable for all kinds of outdoor activities such as mountaineering, skiing, fishing, jogging, hunting, cycling, hiking, ect. Designed with tourmaline technoligy, which automatically heats up in cold weather to make your feet warm and relax. With massage function, this self-heating socks can also eliminate damp heat, remove cold, eliminate blood stasis, relieve leg fatigue, and relieve pain of your foot. A great gift for your parents, lovers and friends, keep your feet warm all day. Specifications: Material: polyester fiber Color: black, white, red(optional) Size: free size Package size: 12*8*6cm Package weight: 40g Package List: 1 pair of Self Heating Socks