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.