Ust - Ultimate Survival Technologies - Reusable Hand Warmer

We use these to keep orphan kittens warm (slip one into a stuffed toy to make it a warm thing to cuddle). They have worked well, and are rechargeable many times. They should not be stored in their crystallized state. Always boil and melt the crystals before storing them, or they will lose the ability to be recharged. Over time, they lose the ability anyway, but we used one for several years before it went bad.

I'm really impressed these are way better than the ones you have to shake up. Plus the fabric or chemicals in those ones makes my hands itchy. It took me awhile to figure out how to activate these tho, you really have to bend the metal disk to get it to work a small click won't work. And these are reusable just put them in lightly boiling water for a few minutes until it dissolves back to liquid.

Bought 5 of these on clearance for $0.75 each. Teseted them out. They work really well.

We use these over and over. Have a few, boil them at once. Have used them several times.

I bought 2 for my high schooler for when she has to wait for the bus. Had really high hopes like "I hope this keeps her hands warm." Not realizing my hopes should have been more along the lines of "I hope this doesn't explode on a snow day soaking her scarf." "Or "I hope this actually works and doesn't freeze." So, bought 2, one froze and the other exploded soaking her scarf.