Little Hotties Foot Warmers 20 Pair Insoles Medium /Large Contains 20 pair of foot warmer insoles. Provide instant heat for up to 5 hours. Air activatedgenerate heat fast All natural ingredients, safe, no odor. No batteries, no microwaves, no fuels M/L fits Women's 9+, Men's 8+ Great for cold weather activities like hiking, camping, ice fishing, etc. LITTLE HOTTIES WARMERS are used by athletes, sportsmen, skiers, construction workers and anyone wanting to stay warm during outdoor activities