HotShotz 35H Reusable Hand Warmer-3/Pack

HOTSHOTZ heat packs are instant, portable reusable and MADE IN THE USA! With the push of a button your HotShotz heat pack will instantly crystalize right before your eyes and heat up to 130º F.
HotShotz heat packs are made from a non-toxic food grade solution encased in medical grade vinyl. They are safe and environmentally friendly. With proper use and storage your HotShotz heat packs will last a lifetime.
Now you can have instant soothing heat anytime anywhere without the inconvenience of a cord or microwave. When your HotShotz heat pack is no longer producing heat just place it in a pot of boiling water and it will rejuvenate back to its liquid form. Your HotShotz heat pack is now ready to activate again WHENEVER AND WHEREVER YOU WANT!

How it Works
HotShotz Heat Packs contain food-grade sodium acetate and water (H20). Sodium acetate is very good at super-cooling. It freezes (solidifies) at 130º F (54º C), but will remain as a liquid at a much lower temperature and is very stable. Clicking the disk, however, forces a few molecules to flip to the solid state, and the rest of the liquid then rushes to solidify as well. The crystallization is an exothermic process, the resulting ice is hot. The temperature of the solidifying liquid jumps up to 130º F during this process. When you boil the solid, you melt it back to the liquid state. You must completely melt every crystal, by the way, or the liquid will quickly re-solidify. You can repeat this cycle forever, theoretically, just as you can freeze and melt water as many times as you like.