Heat Pack Back Strap

Description

Now you can be completely mobile with the HotShotz Back Strap. It has a pocket to slide the 8×12 heat pack into. Not only does it provide you with complete mobility but also helps to insulate and prolong your heat.With a click of the activator button, you cause a few of the molecules to become solid, thus triggering a chain reaction. In the process of going from a liquid to a solid, the by-product is heat. These heat packs are fun to watch. HotShotz Heat Packs contain sodium acetate and water. 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 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 have to 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.