How Hand Warmers are Made

What’s inside a hand-warmer? Wonder no more.
Publish date:
Social count:
What’s inside a hand-warmer? Wonder no more.
Hand Warmers

Admit it. You’ve used them. Don’t be ashamed. When the slopes turn into an icy hell, hand-warmers provide welcome relief. But they aren’t magic. A hand-warmer’s air-activated instaheat is more 10th-grade chemistry than high-tech trickery. In case you slept through class, here’s the fire behind Little Hotties Hand Warmers.

Iron Powder
Iron + oxygen + water = rust. The chemical reaction that turns iron into rust creates heat and is the secret behind hand-warmers.


When a hand-warmer is exposed to air, iron and oxygen ions combine, releasing energy. There is a tiny amount of water in the pouch that acts as the medium for the process to occur.


Salt, an electrolyte, improves the movement of electrons across water, speeding up the exchange between the iron and the oxygen. The result: instant warmth.

Activated Charcoal

Like a mini-barbeque, processed charcoal helps disperse the warmers’ heat, roasting your mitts.

A common fireproofer, vermiculite retains moisture and insulates, which is why your warmers are still cooking after five hours.


Black, or gray…black, or gray?  Not too long ago that was pretty much the only choice shoppers had when perusing the ski glove wall. But more and more vibrant colors are returning to ski gear, and that palate is moving onto the hands, too. Swedish glove crafter Hestra is leading the charge, working with pro skiers to cater to a younger, bolder market.

Hot Hands

Hestra brings the rainbow to next season’s glove line. We’ve got a preview.

Pro skier Lexi Dupont

Healing Hands

This pro skier-designed mitten does more than keep your digits toasty.