Hotteeze: Better Living Through Chemistry

Hotteeze_Self_Heating_Pad I love science. When I was a kid, a large part of my weekends were spent attempting to find the most potent combination of household chemicals. Baking soda and vinegar was too tame for me, and the holy grail of diet coke and mentos hadn’t been discovered yet.

I remember anticipating the arrival of Jeremy’s home chemistry set with ‘bated breath, but the stark reality was deflating. Even in the eighties, namby-pamby, politically correct mail order companies didn’t send sodium and oxidising inorganic compounds to 10 year olds. Spoilsports.

I can imagine if Hotteeze had been around at that time, a number of packs would have been purchased by Team Chemistry Papatoetoe. These heat pads use nothing but chemistry to warm up to a toasty 40 degrees and stay that way for 12 hours. As far as I can tell, it’s a combination of iron powder and potassium chloride, mixed with a couple of inert compounds (carbon and vermiculite) to slow down the reaction.

I was expecting some sort of action to start the reaction, like breaking the cartridge in a glow-stick. Instead, you just open the packet and wait. The reaction with air causes (I imagine) the reaction to start, and within about 15 minutes the pad is warm to the touch. Stick them in your pockets or shoes, and you’ll be toasty. I can imagine they’d be pretty damn nice to have in your ski boots.

When you’re finished, the resulting compound is completely inert, and makes a good soil conditioner for your garden. The outer packet isn’t biodegradable, but Hotteeze say it is “combustible, and does not generate dioxin”, which is OK I guess.

You can buy Hotteeze online here.

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  1. Oh absolutely, if you’re going hiking (tramping to Kiwis) or off-piste and want an emergency warming pack then this is definitely the thing to take. But for something to have in your backpack for those days when you’re stuck at the bus stop and the water’s dripping down your neck, the rechargeable type seems like a better idea.

    Frankly I think the chemistry in both is pretty cool.

  2. You are right Ben, the chemistry set was a bit lame, after I had burnt all the magnesium ribbon there was not much left (a big tube of Cobalt Chloride, and lame Alum) The little burner was very cute though. I found much better chemicals at Mitre 10 *Andrew’s Salts* ahem.

    I do like those hot packs, but I would prefer the Sodium Acetate ones, I like the reusability, but I can’t find any in stores.

    BTW great site, keep up the good work

    Long time lurker/ very old friend

  3. Hi Ben,

    Where can I get these from? Heading down to Ruapehu next week, would love the shoe pads in my boots!

  4. Hi Ben

    I would also like to know where I can get these (and the rechargables). We had been given some by a Japanese friend, but didn’t realize they were on sale in NZ. My husband fishes on winter nights – up in the high country – rain, hail or snow!


    Vivienne Bell

  5. Heh. That’s why they’re called Hotteeze. Cos they’re for the laydeeeeez.

    If you must know, they were invented some time ago in our top secret lady science labs by top secret lady scientists, originally as a “monthly hassle” application… but now we have unleashed them onto the market to see what the rest of you do with them.

    Shoeeeeeezzzze-warmers, indeed. 🙂

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