The ultimate luxury. toasty feet! Herbal Booties are made of ultra comfy polyester suede & cozy shearling. Warm or cold therapy provides soothing relief from strenuous exercise or from an average day s pounding. A physician formulated blend of 12 soothing aromatic herbs and 100% natural grains retain heat to keep you warm relaxed & comfy. One size fits all. Microwave for instant heat therapy or chill for instant cold therapy. Feature:. soft & cozy fabric. heats in microwave in minutes. great for active people with sore tired aching feet. 100% all natural herbs & grains in sole of Bootie. long lasting penetrating warmth. perfect for sore tired feet. chill in freezer for cold therapy.