Reusable handwarmers that get hot by freezing

These things are so cool they're hot.

Here's some links.
Technology Connextras (the second channel that stuff goes on sometimes):

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[TechnologyConnections]

Hi! Through this video, we've apparently uncovered another one of those fun continental divides. It seems the reusable kind is quite common across Europe, and the disposable kind is almost unheard of! Wouldn't ya know. Since I assumed the situations were similar, I'll add that the most significant advantage of the oxidation-type is that they last _hours_ and not minutes. During the B-roll shooting, the handwarmer you saw me open was still nearly as hot as a freshly-opened one 4+ hours later! And these were very cheap.
It's through that lens that I made the judgment that the reusable kind are pretty meh - I'm simply accustomed to something that will reasonably last an entire workday. My take is that given the sustained heat output and fairly inert materials the disposable ones are likely roughly on-par to the reusable ones with regards to environmental costs, especially when you factor in energy spent to re-activate the reusable ones. But that's just my opinion! I hardly use these things at all, really, so I've got no skin in the game.

[theslowmoguys]

Used to shove these in my gloves for my walks to school as a small English child. Although pretty good for the journey there, you end up walking home with cold pebbles in your pocket.

[StrokeMahEgo]

You can reuse the rust in the used "non-reusable" ones to make thermite, which of course, releases even more heat.

[TechStuff]

My young son recently tried to “recharge” a HotHands in our microwave. Ten seconds later he learned an important lesson and I bought a new microwave.

[himssendol]

Those liquid hand warmers were a must have during my childhood. We used them everyday during winter. You’d used them straight from the pot on your way to school and then pop the metal coin on the way back home.

[amberbutitta]

Alec: "Don't buy these"

*more and more accumulate in front of Alec as the video progresses*

[JakHart]

"Fortunately, I have scissors, and a propensity to ignore safety instructions."

Heck yes!

[Robert_DROP_TABLE_students--]

Havent we been trough this? The spent single-use ones are not browner, they are oranger with just as little context.

[BriWhoSaysNi]

I have a pair of earmuffs with little pockets on the inside that each fit a small reusable warmer. I think it's actually a pretty clever use of them. They're in a fabric pouch so they're insulated from the outside air and aren't directly against my skin. And even once the warmers themselves stop generating heat, the earmuffs help to hold in the heat they did generate for longer. Great for walks on cold days!

[TomatePasFraiche]

"It's rust, how iron-ic" we are getting so much layers guys! Very nice

[hardluck]

"It got a *lot* browner" - no no no!
It got more "orange with context"...

[tfsho]

"I have scissors and a propensity to ignore safety instructions"

I need that on a shirt 🤣

[rays]

My parents used to have one of these back in the '90s. We would used it to warm our hands after horseback riding in the winter. It was clear, and turned white when activated. I remember how they used to have to boil it on the stovetop after every use. I also remember how hard it got: not quite like a rock, but like certain plastics, maybe even PVC.

But tell the truth. The way they work is that each one has a magic wish-granting genie inside, whom we have enslaved and commanded to generate heat each time we squeeze the disk. It's a good thing you didn't cut one open to show us the liquid on its own, because you would have freed the genie, and he would surely have killed you.

[michealpersicko]

Fun fact: Zippo currently sells a refillable pocket warmer that uses zippo fluid as a fuel source. It uses a catalytic heater inside to allow it to burn without fire and the case has vent holes to draw in enough oxygen to keep it warm in its bag in your pocket for 6-12 hours depending on what size you get.

[notafantbh]

4:18 Opportunity to say "These, on the other hand" while holding the other hand warmer in the other hand LOST

[adamfazar]

“Fortunately I have scissors and a propensity to disregard safety instructions”- my new life motto

[Ella]

0:45 I remember when I was a teenager, my dad got one of those, and that was my exact thought. “A reusable hand warmer! Cool! Oh… the heat lasts like 5 seconds. And you have to boil it every time…? Neat concept. I’ll stick with my Hot Hands” 😆

[kerielwatson]

My fam uses these for hiking when it's snowing on mountain peaks. I use the non-reusable ones but it's a brand that actually does say you can open it once it's used as the contents can be tipped on the garden and the pouch is compostable. Woot.

[Wattstone]

2:10 - "Open, rupture or tear". Well, they didn't say 'cut', so I think you're in the clear.

[pacAliveSrbija]

The blue is more squishy to be more bouncy and the orange is harder to be more slippy. Cave is truly a genius