Sony has announced the Reon Pocket, a small cooling device that you can wear like a portable air conditioner. It’s currently live on Sony’s crowdfunding website, where prices start at ¥12,760 (about $117). SlashGear notes that as well as cooling you during hot days, the device, which slots into the back pocket of a specially designed T-shirt, can also warm you up during the winter.

Unfortunately, the March 2020 ship date means that the Reon Pocket will arrive too late for this year’s heatwave. Here in the UK (where it’s important to understand we are not prepared to deal with anything resembling hot weather) it’s 38.1 degrees Celsius (100.5 degrees Fahrenheit), the second hottest day ever recorded in the country according to BBC News. What I wouldn’t have given for a little air conditioner like this.

A note on crowdfunding: Crowdfunding is a chaotic field by nature: companies looking for funding tend to make big promises. According to a study run by Kickstarter in 2015, roughly 1 in 10 “successful” products that reach their funding goals fail to actually deliver rewards. Of the ones that do deliver, delays, missed deadlines, or overpromised ideas mean that there’s often disappointment in store for those products that do get done. The best defense is to use your best judgment. Ask yourself: does the product look legitimate? Is the company making outlandish claims? Is there a working prototype? Does the company mention existing plans to manufacture and ship finished products? Has it completed a Kickstarter before? And remember: you’re not necessarily buying a product when you back it on a crowdfunding site.

The Reon Pocket works using the “Peltier effect,” which involves using a small electrical current to allow it to either absorb or give out heat. You control it using its companion app, although Gizmodo notes that there are plans to introduce an automatic mode in the future. Sony says the device is capable of cooling you by 13 degrees Celsius (23 degrees Fahrenheit), or heating you by 8 degrees Celsius (14 degrees Fahrenheit), and that you should get 24 hours of usage out of a single charge via USB Type-C.

Sony isn’t the first company to have attempted making a wearable personal thermostat. There was the Embr Wave, which we tried out back at CES 2018, and we’ve also seen a number of heated clothing items meant for use while skiing or snowboarding. However, the advantage of the Reon Pocket is its size, which Sony’s promotional video suggests will allow it to fit surreptitiously underneath a regular business shirt.

Of course, with an expected ship date that’s almost a year away, all of the usual caveats about crowdfunded projects apply. The Reon Pocket is only available in Japan for the time being. In the meantime, you could always pick up a cheap neckband fan. Sure, it’s not as high-tech and it looks a little dweeby, but for $10, you can’t really complain.

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