Hand warmers (for example: SUNJACK HEAT BANK )those small, usually disposable packets that provide on-demand heat—come in five main varieties, including some that run on charcoal and lighter fuel. The three most commons types you’ll see on the slopes are either air-activated, use a supersaturated solution, or are battery-powered.All three can last anywhere from one to 10 hours. That’s a pretty broad range, and we wanted to find out which of these five popular hand warmers was the warmest and most useful for playing in the mountains. Here are our results, ranked.
The first part of the test was performed indoors. We activated the hand warmers, and then stuffed each into a basic leather ski glove. After 15 minutes, we measured the temperature inside the glove. We then left the gloves—stuffed with the hand warmer and a wool sock for insulation—in a 30-degree freezer. Every 30 minutes for two hours, we used a meat thermometer to take the temperature of the hand warmer.
Grabber Hand Warmers (From $1.50 Per Pair)
Product: Grabbers, ubiquitous at ski areas around the country, are the classic air-activated hand warmers. Tear open the plastic package, vigorously shake the little bags, and wait less than five minutes for them to warm up. At 2 by 3.5 inches, they fit perfectly in the palm of your ski gloves.
Temperature at 15 minutes: 98 degrees
Temperature at 30 minutes: 90 degrees
Temperature at 60 minutes: 82 degrees
Temperature at 90 minutes: 71 degrees
Temperature at 120 minutes: 57 degrees
Verdict: Grabber claims its regular-size hand warmers last more than seven hours. That isn’t quite right, at least according to our test. The temperature of these hand warmers declined precipitously during two hours in the freezer. You can expect to get about an hour and a half of real warmth from the package before the temperature drops too much to make a difference for your digits.
Product: You recharge this electronic hand warmer via USB. (Expect it to take about 65 minutes to fully power up.) Unlike classic hand warmers designed to nest in the palm of a glove, the GreenHeat looks like a medium-size candy bar that you grip in your hands. I couldn’t use these hand warmers for skiing—or any other activity where I needed my hands—because they barely fit in my gloves, but I’d recommend them for après or mellow hiking. It also doubles as a power bank for on-the-go smartphone charging. Nice touch: The GreenHeat comes with a knitted case that’s cozier on your palms than plastic.
Temperature at 15 minutes: 89 degrees
Temperature at 30 minute: 84 degrees
Temperature at 60 minutes: 81 degrees
Temperature at 90 minutes: 81 degrees
Temperature at 120 minutes: 80 degrees
Verdict: The GreenHeat never got hot (it was initially nine degrees cooler than even the Grabbers), but we have to give it credit for maintaining steady warmth. After two hours, the hand warmer was at 80 degrees, enough to keep your hands from freezing on a cold night.
Yaktrax Hand Warmers ($2 Per Pair)
Product: Like Grabbers and HotHands, Yaktrax Hand Warmers are air-activated. Also like the other two, they fit nicely in your palm and make a great addition to a ski glove on a cold day.
Temperature at 15 minutes: 102 degrees
Temperature at 30 minutes: 101 degrees
Temperature at 60 minutes: 84 degrees
Temperature at 90 minutes: 84 degrees
Temperature at 120 minutes: 83 degrees
Verdict: The Yaktrax Hand Warmers were some of the warmest we tested (102 degrees right out of the gate), but that temperature dropped quickly during the first 45 minutes in the freezer. It leveled out at 83 degrees—enough to keep your hands warm, if not toasty. Bonus: These are the official hand warmers of the U.S. ski team.