Cold hands are just the worst. They're not only extremely uncomfortable, they might also prevent you from using your smartphone! And that's something we simply cannot let happen! To keep you safe during the winter, we've developed the Plutonium Handwarmer! And as true nerds, we've written down every single detail on how you can activate this little nuclear power plant.

Before first use, the inside of the hot pack should be liquid. Push the inner metal plate until it clicks and the crystallisation of the sodium acetate begins. Through this, the liquid becomes firm and emits the saved energy as heat. The "plutonium" reaches a lovely temperature of 53 °C. Just put it into your pocket and brave the cold with no more shivers or fears.

Of course, you'll want to use your hot pack more than once. So, you'll need to charge it with new energy, in a manner of speaking. That requires a pot, water and maybe a spoon. Let the water boil in the pot and put the hot pack into it. Use the spoon to stop the "plutonium" from sticking to the bottom, if needed. Heat the hot pack until all the crystals are liquid again – should take about 5–10 minutes. As soon as the hot pack is cooled down, it's ready for use again in the great barren and cold outside.

Please note: Due to the metal inside, the hot pack must NOT be heated up in the microwave. And obviously, the handwarmer does not contain actual plutonium – it's just modelled after the element's symbol from the periodic table. Sorry, dear IAEA ;).