My Favorite Rechargeable Hand Warmers Are at an All-Time Low Price for Prime Day
When winter weather comes around, you'll probably find yourself looking for new options to keep warm, from choosing toasty winter workout gear to finding the best setting for your thermostat. One of my favorite solutions year after year is a pair of rechargeable hand warmers that slip right into your gloves.
I used to buy those disposable pouches to keep my fingers from freezing -- you know the ones, with chemicals that heat up when you expose them to air. And though they did help me stay warmer when I was outside, I always felt bad about throwing away each single-use bag and its plastic packaging.
Now I've ditched the powdered packets in favor of rechargeable warmers -- specifically, a pair of Ocoopa UT3 Lite Magnetic Rechargeable Hand Warmers. With USB charging and multiple temperature levels, these compact hand heaters keep my palms and fingers toasty for hours. When their energy is used up, I just top off the power to use them again later.
They come in a variety of colors, and prices between $16 and $30. I bought the orange ones (because orange, of course), which are currently $18.
The included lanyards make it easy to keep the warmers nearby.
Jeff Carlson/CNET
Essential Ocoopa UT3 Lite specs
Here are the details about these little warming wonders.
Battery capacity: 5,000 mAh
5,000 mAh Temperature range: 100 to 125 degrees Fahrenheit
100 to 125 degrees Fahrenheit Input: USB-C (with rubber dust cover)
USB-C (with rubber dust cover) Size: 3.39 inches by 1.89 inches by 0.71 inch
3.39 inches by 1.89 inches by 0.71 inch Weight: 65g each
65g each Included: Two hand warmers, two wrist-length lanyards, USB-C to USB-C cable
Two hand warmers, two wrist-length lanyards, USB-C to USB-C cable Charging time: Three and a half hours
Three and a half hours Materials: Aluminum heat surface, plastic body
Why I chose the Ocoopa UT3 Lite hand warmers
In addition to creating less waste, a rechargeable hand warmer offers several advantages over the disposable ones.
The Ocoopa UT3 Lite has three temperature settings, which range from around 100 to 125 degrees Fahrenheit. In most cases the first setting is adequate, but sometimes I'll kick it up to the middle, which is around 109 to 117 degrees. I haven't yet kept it at the third setting, but as a Seattle resident, I also haven't yet ventured into really cold conditions.
They also heat up quickly, in just a few seconds. Packet warmers usually take 15 to 30 minutes to get warm.
Hand warmers are typically sold as a pair. Just the front of each UT3 Lite heats up, but the back is a magnet so you can attach the two to use as a double-sided heater.
Snap the two warmers together via their magnetic backs.
Jeff Carlson/CNET
When I'm out in the cold, I usually keep them in my coat pockets, where I can grip them when I'm not using my hands for anything else. But they aren't only used out in the elements. My attic home office stays pretty chilly if the temperatures are low outside, even with a space heater running. Having these rechargeable hand warmers nearby keeps my hands toasty, like cradling a hot beverage (since unfortunately it's impractical for me to make espressos all day).
Hand warmers don't need a complicated interface
Each UT3 Lite includes one button and one charging port. And I'll admit that the fact these use USB-C ports was a significant part of my purchasing decision. I dream of a near future when all my gadgets are USB-C powered or connected. Unfortunately the port is only for charging the warmer itself. Some warmers can also charge a connected phone or other device, but I have a handy Anker 622 USB charger for that.
The USB-C port is shielded by a rubber cover.
Jeff Carlson/CNET
The single button powers up the warmer and switches between heat levels: Press and hold to turn on, and then single press to switch between the three heat modes. Tiny lights above the button indicate the warmth level in red; when charging, the lights turn blue and show how full the battery is. The lights are almost too tiny, though, requiring me to get the right angle to spy which heat level is active.
The indicator lights are almost too small, but they do the job.
Jeff Carlson/CNET
Hand warmer size turns out to be important
The Ocoopa UT3 Lites are small enough to slip into a glove or a pocket, which is appealing. Many other warmers are larger and bulkier. I imagine these would be great for skiing or snowboarding.
How long do these hand warmers last?
Each warmer emits heat for between four and eight hours, depending on the warmth level. That's less than many alternative warmers on the market (which can run for 10 to 13 hours), but it's not surprising given the physical sizes. Packet warmers tend to last around 10 hours.
Yes, there are a lot of alternative hand warmers out there
Although I often run across people who've never heard of rechargeable hand warmers -- "What is that, a new phone?" -- the product category has been around for several years. And there are a lot to choose from at various price points and options.
I previously picked up a pair of hand warmers by JMOSTRG -- currently $25 at Amazon -- because they also include an LED light, LCD display and a port for topping up an iPhone. After all, a hand warmer is basically a big rechargeable battery that puts out heat.
Jeff Carlson/CNET
But in practice it tries to do too many things. Although the warmer itself charges via USB-C, the port to power a phone is USB-A. Controlling the heat output, and whether it applies to one side or both, involves remembering several combinations of button pushes and long-presses. I wanted to warm my fingers from the heat, not from moving them around so much trying to get the right setting.
I'll still toss them into a suitcase or bag as backup, but they ended up being too fiddly for more regular use, in my opinion.
Instead, my Ocoopa UT3 Lites are the perfect balance of size and simplicity, helping me brave the elements -- even if that's just a slightly drafty workspace.
For more ways to stay warm in winter, check out this different kind of heat pump, and consider a heated blanket. And for more awesome tech deals, skim our running coverage of the best Amazon Prime Day deals.
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