HotSnapZ Reusable 4" Hand Warmers INSTANT HEAT WITH NO ELECTRICITY - Snapping the internal starts to generate instant heat, reaching up to 130 degrees. The internal chemical reaction generates long-lasting heat (about 30 to 40 minutes). Heat when you need it fast. QUALITY - All HotSnapZ product come with a Lifetime Warranty. Selling online since 2003. REUSABLE - Stop filling up landfills with disposable hand warmers! Recharge by boiling your HotSnapZ in water for 10 to 15 minutes. Remove and allow to cool to room temperature. They are then ready for use again and again. AMAZE YOUR FRIENDS AND FAMILY - When you first see or show them to somebody, you'll know what we mean. They have the "WOW" effect. LIFETIME WARRANTY