Skiing or trudging through miles and miles of snow during a hunt can be hellish if your soles are not adequately protected from the cold. If your feet are the areas in your body that are most vulnerable to the cold, then it's time to get yourself a pair of Hotronic FootWarmer S4 Universal. Check out the S4's features below to know if these foot warmers are perfect for you.

Features:

* Universal fit. The Hotronic Footwarmer S4 is available in two designs: custom and universal. Unlike custom heaters, Hotronics highly rated universal foot warmers offer a distinct advantage as you can easily trim the insoles and the Cambrelle covers to ensure that they fit inside your ski boots or hunting boots. If you wear custom orthotics, then you're in luck as these boot warmers work great with them. The footwarmers' universal fit also allows you to wear them inside different types of winter footwear

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* Reliable heating elements. These foot warmers are equipped with a pair of large oval heating elements for better coverage. They are easy to assemble, and you'll barely feel the heating elements and the wires underneath your feet while you’re wearing your boots (when properly installed, of course).

* Cambrelle covers and strips. The Hotronic Footwarmer S4 Universal comes with Cambrelle footwear lining to ensure that your feet are comfortable and dry all the time. Unlike other types of lining, Cambrelle doesn't wear down easily because of its high abrasion resistance. Plus, the covers and strips are self-adhesive for hassle-free setup.

* Variable heat settings. Go from comfortably toasty to super warm in seconds with the footwarmer's variable heat settings. You can set it on low (average temperature ranges from 84 °F to 98 °F) when it's not as chilly. Or set it on high and experience an average temperature ranging from 158 °F to 173 °F.

* Powered by rechargeable AA NiMH cells battery. The Hotronic Footwarmer S4 Universal is unique because the boot heaters come with a pair of rechargeable NiMH AA cells batteries. These are high capacity batteries that do not require to be fully discharged before you recharge them. They come with their own charger, plus their own US and European adapters so there's no need to search for an electronics store when you're skiing or snowboarding in other countries.  

The Hotronic Footwarmer S4 Universal is perfect for skiing, snowboarding, hunting, camping, or any other outdoor activities during winter. But the heating element and the Cambrelle covers can be challenging to install so set aside an hour or more during the day to set them up.

The batteries are strapped to the boots with the help of brackets and their installation can also take some time. The positioning of batteries makes them a bit of a hassle to access.

You don't have to worry about cold feet whenever you go out to ski, hunt, or snowboard thanks to the Therm-ic 1700 Bluetooth Heated Insole Kit. This kit is equipped with everything you need to ensure that your feet are nice and warm even when there's a cold snap or blizzard outside. Find out what makes this heated insole kit a great investment this winter.Features:

* Light and super-fine heating elements. Make sure your insoles are always warm even when there's a blizzard outside with Therm-ic 1700's heating elements. Positioned underneath the Therm-ic insoles, they are crafted to be super fine and extremely light so you'll hardly feel them when you place them inside your boots.

Worried that you won't be able to integrate them into the insoles or orthotics you're using right now? Don't be, as these heating elements are designed to be used with just about any insole or custom orthotics.  

* Up to 17 hours of heat. The Therm-ic 1700 Bluetooth Heated Insole Kit comes with a pair of C-pack batteries that can power up the heating elements for as long as 17 hours. Now you can ski all day and still have plenty of time to keep your feet warm until you and your friends call it a night. The batteries have a USB charger and would take anywhere between three to five hours to charge.

* Therm-ic Heat Control App and Bluetooth control. The power/temperature button is located on the battery itself, so reaching for it can be a hassle especially if you're holding your ski poles, a rope, or your phone. It's a good thing that Therm-ic has developed the Heat Control App so you can control your device from your smartphone.

Simply download the app, connect it to the battery pack via Bluetooth, and you're ready for a warmer winter.The Therm-ic 1700 Bluetooth Heated Insole Kit is one of the priciest products on the list because of its longer battery life, app control, and Bluetooth integration. If you don't mind the high price tag, the go for these heated insoles.

* Trimmable insoles. The Thermacell Heated Insoles can be easily trimmed to fit your winter boots. Plus, the top layer material and lining are water-resistant so you don't need to fear that the heating element will be damaged in case a little bit of water seeps into your boots while fishing or sailing. You can use your boots’ removable insole as a pattern if you're going to trim the Thermacell Insoles.

* Lightweight heating element and battery. Unlike other products on the list, the heating element and the battery are sandwiched between the materials so you get lighter, more comfortable insoles. Just slip the insoles inside your boots and you're ready for your adventure.

The heating element is ultra-fine so you'll barely feel it underneath your feet during your activity. The battery, which is hidden underneath the ball of the foot, is also not as bulky as other batteries on the list. Because the battery is hidden in the insoles, you don't have to deal with wires and complicated installation instructions when using the heated insoles for the first time.     

* With remote control. Don't you just hate it when you need to put down whatever you're holding and reach down to your boots or knees to adjust the temperature of your heated insoles? Thermacell gets rid of all the hassles of fumbling for the temperature adjustment button when you're in the middle of an adventure thanks to the insoles' handy remote control. It has two variable heat settings that can go from medium to high.  

* Warmth of up to 5 hours. You can engage in winter sports all morning long thanks to its high capacity battery which lasts up to five hours. The heat can be as low as 100° F or you can it on high (111° F) if you want. To turn it on/off, simply use the switch at the back of the heel or just use the remote by pressing the "No Heat" button.

Keep in mind that the Thermacell Heated Insoles can be bulky, so wear these insoles with shoes one or a couple sizes larger. Also, trim the insoles carefully so you won't damage the heating element inside.

Features:

* One-size-fits-all and trimmable insoles. The Hotronic Foot Warmer S3 Universal comes with one pair of insoles that you can trim to fit any winter footwear. Want to wear them inside your riding boots? Just trim them to fit the boots. Need the foot warmers inside your ski boots? Simply install them inside the boots are the insoles are already trimmed to fit.

* Self-adhesive covers and strips. The self-adhesive covers protect your foot from coming into direct contact with the heating elements. You can trim the covers to fit the Hotronics insoles, or you can attach them to your boots' own insoles or your orthotics.

 * Light and super-fine heating elements. The Hotronic Foot Warmer S3s come with large oval heating elements for better coverage. They are extremely light and ultra-fine to ensure that you'll barely feel them while skiing, fishing, or riding your bike. The heating elements offer 3 regular heat settings, plus an additional timed setting if you want to take warmth to a whole new level.

* With high capacity AA NiMH cell batteries. The heating elements are powered by a pair of high capacity AA NiMH cell batteries that can last for more than 17 hours when set on low and more than 3 hours when set on high. Unlike lithium-ion batteries, you don't need to fully discharge the Hotronic batteries before charging them again.

* With US and European adapters. Many heating elements come with a US charger only, making it a hassle if you're skiing abroad. Now you don't need to look for an electronics store during your dream ski trip in Finland or Switzerland to find an adapter as the Hotronic Foot Warmer S3s come with their own charger with US and European adapters.Note that the Hotronic S3 heating elements are smaller than the S4 system.

The batteries are strapped to the boots so it can be a hassle to turn the heating element on or adjust the temperature if you're lugging around a heavy backpack or gear.

Features:

* Ultra-light ergonomically designed insoles. The insoles have a thickness of 0.5 cm at the toes and 1.2 cm at the arch so you can easily fit them inside your ski boots or even just your regular leather boots. The insoles are made of durable EVA, but they are soft enough so they can be trimmed to fit most of your winter shoes.

* Fine heating element. These heated insoles come assembled already so you don't have to spend an hour or more putting together insoles and heating elements inside your boots. The heating elements are sandwiched between the EVA layers and radiate the warmth of up to 140 °F. The battery lasts between three to seven hours, and power is provided by a dual micro-USB charger (included in the package).

* Three heat level settings. The Dr. Warm Heated Insoles let you customize the warmth the heating element radiates thanks to the three heat level settings (low, medium, high).

* With remote control. These heated insoles stand out because you don't need to reach down to your boots just to adjust the temperature. Set the temperature from low to high with the handy remote control. Although they look promising, the Dr. Warm Heated Insoles under-deliver.

The battery does not last very long, while the heating elements tend to underperform. They are also a bit expensive, so explore your options before ordering these heated insoles.

Features:

* One-size-fits-all Cambrelle covers. The Therm-ic C-Pack Set 1300 boot heaters take away all hassle of finding that the items you've bought online are the wrong size. The pack has a pair of one-size-fits-all Cambrelle covers that you can easily trim to fit most of your winter footwear.

The durable Cambrelle covers not only ensure that the warmth generated by heating elements are distributed evenly, they also ensure that your feet are dry and comfortable the whole time.  

* Ultra-fine heating elements. One of the most common issues about boot heaters is the bulk--you can sometimes feel them beneath your soles when you're in the middle of an activity. The Therm-ic C-Pack Set 1300 features a pair of ultra-fine and lightweight heating elements that you will barely feel when they're positioned properly underneath your soles.

 * Powered by a pair of high capacity C-pack batteries. Each heating element is connected by wire to a high capacity C-pack battery. The battery provides up to 13 hours of heat, making it ideal for hunters, skiers, and ordinary people who just want their feet warmer for longer. The power/temperature adjustment button is located on the battery itself.  

* With USB charger. The Therm-ic C-Pack Set 1300 boot heaters come with their own USB charger so you can power them up anytime, anywhere.The Therm-ic C-Pack Set 1300 boot heaters are less expensive than the Therm-ic 1700 as the heating elements are not connected to the app and do not offer Bluetooth connectivity.

But these boot heaters will do if you don't mind reaching down to your boots whenever you want to adjust the temperature. It would also take some time to install them so spare an hour or two if you’re going to set them up.

Features:

* Unisex heated insoles. Whether you're buying them for yourself or for a friend, you'll never have to worry that you might get the wrong pair as these heated insoles are designed for both men and women. Even better, you can trim the toes and sides (just be careful not to cut the heating elements inside!) to make sure that they fit inside your ski boots or hiking boots.

* High-efficiency carbon fiber heating element. The J-Jinpei Heated Insoles come with a pair of high-efficiency carbon fiber heating element. These are installed between the upper and lower layer of the insoles so what you get is a comfortable warmth that spread from the arch of your foot to your toes.

* High-capacity lithium-ion polymer batteries. Apart from the heating element, the insoles also store the high-capacity and ultra-slim lithium-ion polymer batteries. When you set it on low, you can expect the batteries to work for as long as 7 hours, giving you plenty of time to ski, snowboard, or hunt throughout the day. If there's a cold snap and you're going to set the temperature on high, then expect the batteries to last for as long 3.5 hours of continuous use.

* With remote control. Reaching down to your boots to adjust the temperature of your heated insoles can be a difficult especially if you're holding your winter gear. Thanks to J-Jinpei Heated Insoles' remote control, you don't need to reach down to your boots to adjust the temperature. Simply press a button on the remote control to turn it on/off, as well as adjust the temperature.

What makes it stand out is the digital display which lets you know the exact temperature of your heated insoles.The remote control, the low price, and the ultra-thin design are some of the main selling points of the J-Jinpei Heated Insoles.

 If this is your first time buying heated insoles and you don't want to spend a lot of money on them, then these heated insoles are a great choice.

Features:

* Powerful lithium-ion batteries. The Therm-ic SmartPack RC1600 battery pack includes a pair of powerful and high-capacity lithium-ion batteries. What makes them stand out is their compatibility with all Therm-ic insoles and even other heating systems manufactured by Therm-ic. The warmth lasts up to 29 hours, so you can stay and play outside for longer.

* Lightweight and easy to install. Hiking boots, ski boots, and other types of winter boots are already heavy. Luckily, lithium-ion batteries are lightweight and compact so you won't feel their weight while you're hunting, riding your horse, or skiing this winter. Plus, they're easy to install. Just clip them on your boots, plug them into the heating system, and turn them on.

* Convenient temperature control. Adjust the temperature from low to medium to high using the battery's built-in temperature control. When you set the temp on low, expect warmth of up to 99F. Set it on high and experience a comfortable 158 °F heat in your feet.

* Remote control included. But if you're going to deal with ropes and other gear during a mountain climbing expedition or you're going cross-country skiing, then reaching down to your boots can be a hassle. Don't worry as this battery pack comes with its own remote control so you can adjust the temperature with just a simple press of a button.

With a battery life that lasts up 29 hours, the Therm-ic SmartPack RC1600 is the most powerful set of batteries in the list. These batteries are perfect if you're going on a long cross-country expedition or you're scaling a high mountain this summer.

Features:

* Compatible with all Therm-ic insoles and other heating systems. If you’ve lost one of the batteries of your Therm-ic heated insoles during a hike or while snowboarding down that slope with your friends, don't worry as you can easily replace them with the Therm-ic SmartPack IC950 battery pack. You don't have to worry that they won't work with your existing Therm-ic devices as the IC950 battery pack is designed to be compatible with all heated insoles and other heating systems.

* Hassle-free installation. Each lithium-ion battery comes with a clip so you can easily attach it on your ski boots or riding boots. Just clip it around the strap of your ski boot or the cuff of your regular boots, plug it into the heating element, and turn the battery on to experience the desired warmth.  

* Lasts up to 18 hours. Unlike regular heated insole batteries that only last up to 7 to 10 hours, the Therm-ic SmartPack IC950 battery pack lasts up to 18 hours (when set on low). If you live in an area where there's a cold snap and you want to set it on high, then expect the battery to last up 3 hours or more.

The Therm-ic SmartPack IC950 is compact and light (it only weighs 3 ounces), so you'll barely feel its weight while skiing, hunting, or fishing. Note that if you want to extend the battery life, make sure to turn it off or set it on low while you're indoors.

Features:

* Slim and lightweight insoles. This set comes with a pair of Thermicsole Classics which are slim and lightweight. Unlike other insoles in the list which are contoured to the foot, the Classics are flat for greater versatility. You can easily trim these insoles so they'll fit inside your ski boots or any other winter boots you have. (But trim carefully so you won't damage the heating elements inside!)

* Powerful heating element. The heating elements are sandwiched between the upper and lower layer of the insoles for better coverage. The heat they produce can go as high as 158 °F, but you can also set it on low by turning it on low (99 °F).

* High-capacity NiMH battery pack. The Therm-ic ThermicSole Classic Supermax Set is a departure from regular heated insoles as these are equipped with high-capacity NiMH batteries (set of 2). The battery life lasts up to 18 hours when set on low, and 3 hours when set on low.

* Includes a global charger. If you have a competition abroad or just traveling to another country, you know how much of a hassle it is to leave your hotel so you can buy an adapter. Therm-ic knows this so this set comes with its own global charger that you can use in North America and in Europe.Make sure that your feet are warm even in extreme conditions with the help of the Therm-ic ThermicSole Classic Supermax Set.

 The heated insoles are especially helpful if you're suffering from Raynaud's disease or other such health conditions. The whole set, however, can take an hour or so to install so you make sure that you allot some time before going out for your adventure.

Features:

* Trimmable insoles that are available in 2 sizes. The Torch Electrek Outrek II heated insoles are available in medium and large. If you want to customize the fit, just get your scissors and carefully trim the toe portion of the insoles. You don't need to worry that you'll reach the heating element inside as the areas you can trim are clearly marked. The insole also wicks moisture, so you don't need to worry about the embarrassing foot odor when you remove your boots.

* Powerful heating element. The Torch Electrek Outrek II's heating element is stored inside the insoles for better warmth and coverage. The temperature can go as high 135 °F when set on high and 113 °F when set on low.

* With rechargeable lithium-ion batteries. These heated insoles are powered by rechargeable lithium-ion batteries located underneath the ball of the foot. They are slim and compact so you'll hardly feel them whenever you're wearing your boots. The battery life lasts anywhere between four to six hours (depending on the heat level setting).

* Set comes with remote control. Adjusting the temperature of the heated insole can be a hassle if you need to sit down and reach to the top of your boots to press the battery's button. With Torch Electrek Outrek II, all you have to do is press a button on the remote control to turn it on or off or adjust the temperature settings.

Now you'll be able to enjoy the great outdoors without fear of cold feet thanks to the Torch Electrek Outrek II heated insoles. Because the battery is located inside the insoles and there are no wires to deal with, it will be easy for anyone to install them inside any closed shoes.

Features:

* Lightweight and durable materials. The soft and abrasion-resistant top layer of the ThermaCELL Proflex Heated Insoles protect the heating element underneath, as well as diffuse the warmth all over your feet. Underneath the heating element is a durable, insulating, and water-resistant fabric liner. Because the insoles are made of pliable materials, you can easily trim them to fit any closed shoes you have.

* Slim and ultra-light heating elements. The ThermaCELL Proflex Heated Insoles are equipped with slim and light heating elements. Since they are integrated inside the insoles, you won't feel them each time you stride. The heating elements produce a temperature that can go as high as 111 °F when set on high.

* Lithium-ion polymer batteries. These heated insoles are powered by light and compact lithium-ion polymer batteries that are stored inside the insoles also. They come with their wall charger and USB cable.

* Bluetooth connectivity and temperature control via smartphone. These batteries of the insoles are integrated so you will have to download the ThermaCELL app and connect the insoles to your smartphone via Bluetooth. Turn the heating elements on or adjust the temperature using your smartphone for a hassle-free adventure.

The light and compact design and the smartphone connectivity make the ThermaCELL Proflex Heated Insoles stand out. But the insoles have battery life issues, and the temperature the heating elements emit are not as powerful compared to other heated insoles.