How to use
UNIHAND hand warmer instructions
You open the box on a mild evening and need warm hands at seven tomorrow morning. Charge both units tonight, learn what the lights mean, and the first cold walk asks nothing of you but a press of the button.
What comes in the box
Lift the lid and you find two warmers and one USB-C charging cable. That is the whole kit, so keep the cable somewhere you will find it again in February. Each warmer is a rounded pebble that fits in your palm, measuring 3.46 by 1.84 by 0.79 inches at about 0.15 lb.
Turn one over in your hand. The face carries a single orange button, next to it sit three small lights in a row, and the shell has a matte, lightly textured grip. Both units are identical in every color, so you never need to work out which one is which.
Charging both units over USB-C
Plug the cable into the first warmer and into a USB charger, then do the same for the second when the first is done. Charge them indoors, at room temperature. Battery University explains that consumer lithium-ion batteries must not be charged below freezing (32 °F) and advises room-temperature charging for ordinary chargers.
So a warmer that spent the afternoon in a cold car should sit on the counter for a while before it goes on the cable. We give no fixed charge time, and we make no claim that the pair can charge a phone. The lights show how much battery a unit has left, which tells you when it is time to plug in again.
For charging habits and summer storage in depth, read how to get 20 hours from a rechargeable hand warmer in our journal.
Switching on and choosing a level
Press the orange button to wake a unit, and keep pressing to move it between the three heat levels. The printed card that comes with the pair lists the exact presses, so keep it with the cable for the first week. Count the red lights to know where you are.
One red light is Low, two is Medium and three is High. You will also see the lights glow blue at times, because the same row reports heating status and remaining battery. For heat, the red count is the one that matters. Start on Low in a pocket and you can always step up. On a cold morning, switch on a few minutes before you step outside, so the shell is already warm when your hands need it.
The UNIHAND heat levels page sets out each range in degrees with its up-to hours.
Splitting the pair or joining it
Two units give you two ways to use the box. Keep one in each coat pocket, or hand one to the person walking beside you. Each unit has its own battery and its own button, so each one runs on its own.
When your hands are cold through, put the two together back to back. The two halves come together as a single warmer the size of your palm, giving off heat on every side, which is the 360-degree warmth we built the shape for. Set both units to the level you want before you close your hands around them. Pull them apart again when you want two.
Looking after the pair
Wipe each shell dry with a soft cloth after a wet day, and keep the warmers out of water. According to the FAA, a lithium-ion battery that gets wet can overheat much like one that is damaged or overcharged. A unit that took a soaking should not go straight back on the charger. Between seasons, keep the pair and its cable together in a drawer rather than in the car, where summer heat is hard on any battery.
Stop using a warmer that looks swollen, leaks, smells hot or has a cracked shell. The Battery Network treats swollen, leaking or overheating batteries as damaged ones that need special packaging, so do not drop such a unit in an ordinary battery bin. Our FAQ covers the rest of everyday care.
| Red lights | Level | Heat range |
|---|---|---|
| One | Low | 95-107.5 °F |
| Two | Medium | 104-118.5 °F |
| Three | High | 118.5-130 °F |
The pairs on this page are part of the UNIHAND collection, and the five colors above were picked for how to use. Compare them side by side.
Questions
UNIHAND hand warmer instructions: questions
How do you turn on a UNIHAND hand warmer?
Press the orange button on the face of the unit. The same button steps it through Low, Medium and High, and the red lights beside it count the level from one to three. The card packed with the pair shows the exact presses.
Can you charge your UNIHAND warmer in a cold car?
Wait until you are indoors. Battery University warns that a lithium-ion cell charged below 32 °F can be harmed for good, even if it looks fine afterward, and it advises room temperature for ordinary chargers. Give a cold unit time on the counter before the cable goes in.
Do you have to use both UNIHAND units together?
No. Each warmer has its own battery and button, so one can run while the other stays off in a pocket for later. Join them back to back only when you want one warmer that heats all the way around.
What do the blue lights on a UNIHAND warmer show?
The row of lights reports heating status and remaining battery, and part of that shows in blue. When you want to know the heat level, count the red lights instead. One is Low, two is Medium, and three is High.
Is it fine to get your UNIHAND pair wet?
Keep it dry. Water is one of the triggers the FAA names for lithium-ion batteries overheating, and the pair carries no water rating. Wipe off snow with a cloth, and let a damp unit dry fully before it goes near the charger.
One more look
Warm hands start with the right color
Compare the ten UNIHAND pairs on one page, each with its price and its rating.