Self-heating:The self-heating principle of the tourmaline at the bottom, with mild heat, and has a warming effect on the feeling of cold feet.Tourmaline can promote the blood circulation of the feet, and the pulse particles can reach deep into the muscles to effectively cushion fatigue unisex:The warm socks design for both men and women with average size.This super elastic and stretchable heated socks with one sizes fits for unisex adults. Soft Breathable Insulated Material:Made of h-quality polyester cotton ,absorbent,breathable,quick-drying,elastic-thicken.The bottom of tourmaline socks has tourmaline design which can self-heating to warm and relax your feet in cold weather. self-heating function:Powerful self-heating function, can increase the temperature by 5-8 in a few minutes, can continue to heat up, and can resist the severe cold of minus 20.The heated socks come with massage points that can stimulate the acupuncture points of the feet to achieve the massage effect. Suitable for outdoor activities:The Self-Heating Socks hold your foot whole day warm and comfortable for cold weather,for hunting,skiing,ice fishing,hiking,maintaining climbing,running,walking dogs,snowboarding,motorcycling,riding and other indoor/outdoor activities.