- Online: www.REI.com
- URL for this product:
- From the U.S. and Canada — Call 1-800-426-4840
- Mon. through Sun., 4 a.m. through 11 p.m. PT.
- International — Call 1-253-891-2500
- Mon. through Sun., 4 a.m. through 11 p.m. PT. English language only.
Hotronic e4 Foot Warmer
Don't fret over cold feet anymore! The Hotronic e4 Footwarmer brings on-demand, battery-powered warmth to your winter footwear.
- m4 comes with all you need to customize your ski, snowboard or hiking boots using insoles of your choice
- Kit includes two battery packs with heat regulators, one pair of heating elements with coverings, and a recharger with American and European adapters
- High-capacity, rechargeable batteries are designed for cold-temperature operation; battery packs attach outside for easy operation
- Features four temperature/durations settings
- Setting level one heats from 83° to 89° F (28° to 32° C) for 19 to 21 hours
- Level two heats from 96° to 106° F (36° to 41° C) for seven to nine hours
- Level three heats from 105° to 116° F (40° to 47° C) for five to 6.5 hours
- Level four: 135° to 144° F (57° to 62° C) for 2.5 to 3.75 hours
- Level four, which can be used in three-minute intervals or continously, is meant for a burst of heat; CAUTION: Using longer may result in burns
- Battery pack LEDs indicate whether power is on or off and selected heating level; lights blink when heating level four is selected to run continuously
- Advanced charging technology prevents overcharging
Imported.
Item 745511
REI Membership
People Also Viewed
Hotronic Snapdry Boot and Glove Dryer- Reduced to: $54.83
- Originally: $79.00
Seirus Hot Ratz Boot Dryers - Pair- Reduced to: $19.83
- Originally: $35.00
| Specification |
| ||
|---|---|---|---|
| Best use |
| ||
| Dimensions |
Hotronic e4 Foot Warmer Customer Reviews
REVIEW SNAPSHOT®
by PowerReviewsPros
- Retains warmth (4)
- Comfortable (3)
Cons
Best Uses
- Downhill (6)
- Sizing:
Feels full size too small
Feels half size too small
Feels true to size
100%
(5 reviews)
Feels half size too big
Feels full size too big
- Width:
Feels too narrow
Feels true to width
100%
(5 reviews)
Feels too wide
- Reviewer Profile:
- Advanced (4), Expert (3)
- Was this a gift?:
- No (6)
Reviewed by 9 customers
Sort by
Displaying reviews 1-9
Pros
- Comfortable
- Easy to adjust
- Easy To Install
- Quality Construction
- Retains Warmth
Cons
Best Uses
- Cold Football Games
- Downhill
- Fly Fishing
Comments about Hotronic m4 Foot Warmer:
Bought these as a gift for my wife for Christmas this year. Was a little hesitant at first because of the price and lack of reviews online. Main reason for this purchase was a 6 day trip planned to Grand Targhee where it is notoriously cold. These were the ticket! With temps dipping well below zero on several days, we were able to stay out a lot longer than we would have without these. We opted just to mount them on her superfeet insoles, so if she wanted to wear them in different shoes she could. Easily adjustable and simple to use. We mounted them on the outside of my wife's boots and never had a problem with them coming loose. We charged them per the directions and have yet to have a problem. Can't wait to by the 100+cm extensions so she can wear them fly fishing this spring.
- Was this a gift?:
- Yes
Pros
- Easy to use
- Lightweight
- Quality Construction
- Retains Warmth
Cons
- Can Come Off
- Expensive
Best Uses
- Downhill
Comments about Hotronic m4 Foot Warmer:
We got these to try to resolve the problem my wife had with cold feet while skiing. Had tried adhesive foot warmers and a boot toe cover that helped some, but still didn't solve her problem. Happy to say these work great. Although expensive, they're worth it when nothing else works. The only issues we had were originally having the units mounted on the inside leg side of the boot on the boot strap because that appeared to be about the only place they would fit. It's easy to hit them together there, and my wife did loose one, although fortunately someone had picked it up and we were able to recover it. Since then she's moved to the front shin area on the boot tongue pullup loop, and has secured the clip with a velcro band she made. That seems to have resolved the problem.
- Sizing:
- Feels true to size
- Width:
- Feels true to width
- Was this a gift?:
- No
Pros
- Relieves Stress
- Retains Warmth
Cons
- Costly
Best Uses
- Backcountry Skiing
- Downhill
- Mountaineering
- Racing
- Resort skiing
Comments about Hotronic m4 Foot Warmer:
Got these for myself last year, and for my family this xmas. Takes the stress of worrying about keeping your feet warm and not frostbitten out of the day. Makes all winter activities much more enjoyable. I carry them with me all the time in the backcountry or when I don't expect to be able to get indoors easily. Great to have an insurance policy against frostbite.
Service and delivery comments:
REI ski shop did a fine job installing.
- Sizing:
- Feels true to size
- Width:
- Feels true to width
- Was this a gift?:
- No
Pros
Cons
Best Uses
Comments about Hotronic m4 Foot Warmer:
These have been a fantastic investment. I had REI install these into my ski boots and have skied with them a few times now. They keep my feet warm in even very chilly conditions. If you have Raynauld's or just get really cold feet when skiing, these are a must have winter item.
- Was this a gift?:
- No
Pros
- Comfortable
- Easy Entry & Exit
- Lightweight
- Retains Warmth
Cons
Best Uses
- Cross-Country
- Cycling
- Downhill
- Racing
- Telemarking
Comments about Hotronic m4 Foot Warmer:
I use these for cycling. Love how the temp is adjustable to use throughout the fall/winter and early spring.
- Sizing:
- Feels true to size
- Width:
- Feels true to width
- Was this a gift?:
- No
Pros
- Comfortable
- Easily adjustable
- Keep feet warm
Cons
Best Uses
- Downhill
- Snowboarding
- Telemarking
Comments about Hotronic m4 Foot Warmer:
I love skiing and snowboarding and do not like to be cold while enjoying those sports. For years I suffered from cold feet on the mountain thinking. Worse yet, on the best days when powder was all over the mountain and my skis were gliding through the fluffy stuff my feet would get the coldest becuase they were constantly submerged n the cold snow. After having a great day of powder runs ruined by cold numb feet I decided I had had enough misery and bought a pair of hotronic foot warmers. It was definitely one of the best decisions about a snow sports accessory that I have every made. Now I can enjoy a full day of skiing or snowboarding and my feet are never cold.
Installation is not the easiest thing to do, but the instructions lay out how to do it pretty well. For my installation I lined up the heating element on a custom insole and made a 3/4" cut in a custom insole for the cord to pass though. I routed the heating pad cord along the bottom of the insole. The heating pad is held in place by the adhesive cambrelle covers supplied. I then made a 3/4" cut in the heel of my ski/snowboard boot liner as close to the bottom as possible. I passed the cord through the cut and routed the cord up the back of the boot. The cord can be easily connected to the battery pack when placed on the front (best) or side (good) of the boot. Don't place the battery on the back of the boot as the ski lift may knock them off.
Bottom line: if you get cold feet on the mountain (not from looking down a steep hill) buy these.
- Sizing:
- Feels true to size
- Width:
- Feels true to width
- Was this a gift?:
- No
Pros
Cons
- Not Warm
Best Uses
Comments about Hotronic m4 Foot Warmer:
I bought Hotronic boot heaters in 2004. The first problem was the battery cables broke, and the salesman at Christy Sports in Breckenridge blamed it on me, and charged for repair. The primary problem with them, however, is that they simply don't work as promised. They do not generate enough heat to do any good. My feet and toes still get numb from the cold. Please do NOT WASTE YOUR MONEY like I did.
- Was this a gift?:
- No
Pros
Cons
- Poor Construction
Best Uses
- Downhill
Comments about Hotronic m4 Foot Warmer:
I have used boot heaters for many years and have found the Hotronics to be poorly constructed. The boot heater cable is very fragile and severs easily. I use them in AT boots in the back country and at ski areas, and with the moving hinge of the boot, the cable slides into the boot and bunches up, therefore causing a bundle of cable in the boot. If I am not careful about loading the chairlift the cable can be pinched and then the boot heater no longer works. The heater itself has pulled apart and was returned to the manufacturer to be repaired and it no longer holds a charge as well as the other boot heater. I would not recommend the Hotronic boot heater if you are in ski boots the majority of the winter.
- Was this a gift?:
- Yes
Pros
Cons
Best Uses
Comments about Hotronic m4 Foot Warmer:
These things kept my toes warm as promised. So much better than the disposable toe warmers. While I use winter cycling boots, if you want to use booties alone, I am sure the M4s will work just fine. I actually put a booty on over my boots; my feet felt like they were in July, though my face felt like February.
- Gift:
- No
- Sizing:
- Feels true to size
- Width:
- Feels true to width
Displaying reviews 1-9
How are we doing? Give us feedback on this page.
-
Camp & Hike
- GEAR
- Backpacks
- Bivy Sacks
- Camp Furniture
- Hammocks and Cots
- Sleeping Bags
- Sleeping Pads
- Stuff Sacks
- Tents & Shelters
- Water Bottles
- Water Treatment
- All Camp/Hike Gear
- GADGETS AND ELECTRONICS
- Binoculars
- Camp Tools
- Compasses
- Electronics
- Flashlights
- GPS
- Headlamps
- Knives
- Lanterns
- Radios
- All Gadgets and Electronics
- CAMP KITCHEN
- Coffee
- Cookware
- Coolers
- Cups and Mugs
- Food
- Plates and Bowls
- Stoves
- Tables
- Utensils
- Water Storage
- All Camp Kitchen
-
Climb
- CLIMBING GEAR
- Ascenders
- Belay/Rappel
- Carabiners
- Climbing Chalk
- Climbing Harnesses
- Climbing Helmets
- Climbing Holds
- Climbing Packs
- Crash Pads
- Rock Protection
- Pulleys
- Quickdraws
- Rock Climbing Shoes
- Ropes
- Caving and Canyoneering
- Webbing and Cord
- Slings and Runners
- Slacklines
- All Climbing Gear
- SNOW AND ICE
- Avalanche Safety
- Crampons
- Glacier Glasses
- Ice Axes
- Ice Tools
- Mountaineering Boots
- Snow and Ice Protection
- All Snow and Ice
-
Cycle
- BIKES
- Cruiser Bikes
- Comfort Bikes
- Folding Bikes
- Kids' Bikes
- Hybrid Bikes
- Mountain Bikes
- Road Bikes
- Urban Bikes
- All Bikes
- CLOTHING/HELMETS
- Cycling Gloves
- Cycling Helmets
- Cycling Jackets
- Cycling Jerseys
- Cycling Shoes
- Cycling Shorts
- Cycling Socks
- Cycling Tights & Pants
- Arm/Leg Warmers
- All Cycling Clothes
- BIKE ACCESSORIES
- Bike Computers
- Bike Lights
- Bike Locks
- Bike Pumps
- Bike Racks
- Bike Trailers
- Bike Trainers
- Hydration
- Panniers/Bike Bags
- All Bike Accessories
-
Fitness
- FITNESS CLOTHING
- Men's Running Clothing
- Men's Swimming
- Men's Triathlon Clothing
- Men's Yoga Clothing
- Women's Running Clothing
- Women's Swimming
- Women's Triathlon Clothing
- Women's Yoga Clothing
- All Fitness Clothing
- FITNESS FOOTWEAR
- Men's Cross-Training Shoes
- Men's Road-Running Shoes
- Men's Trail Running Shoes
- Women's Cross-Training Shoes
- Women's Road-Running Shoes
- Women's Trail Running Shoes
- All Fitness Footwear
- FITNESS GEAR
- Energy Food
- Exercise Equipment
- GPS Sports Watches
- Gym Bags
- Heart Rate Monitors
- Hydration
- Pedometers
- Running Packs
- Strollers
- All Fitness Gear
- FITNESS SHOPS
- Cycling Shop
- Running Shop
- Swimming Shop
- Triathlon Shop
- Yoga Shop
-
Run
- MEN'S RUNNING CLOTHES
- Men's Running Shirts
- Men's Running Shorts
- Men's Pants and Tights
- Men's Running Hats
- Men's Running Jackets
- Men's Running Socks
- Men's Running Gloves
- All Men's Running Clothes
- WOMEN'S RUNNING
- Women's Running Shirts
- Women's Running Shorts
- Women's Pants and Tights
- Women's Running Hats
- Women's Running Jackets
- Sports Bras
- Women's Running Socks
- Women's Running Gloves
- All Women's Running Clothes
- RUNNING SHOES
- Men's Cross-Training Shoes
- Men's Road Running Shoes
- Men's Trail Running Shoes
- Men's Minimalist Running Shoes
- Women's Cross-Training Shoes
- Women's Road Running Shoes
- Women's Trail Running Shoes
- Women's Minimalist Running Shoes
- All Running Footwear
-
Paddle
- KAYAKING
- Kayaks
- Cockpit Covers
- Kayak Accessories
- Kayak Carts
- Kayak Paddles
- Safety Equipment
- Spray Skirts
- CANOEING
- Canoes
- Canoe Paddles
- Canoe Packs
- Canoe Accessories
- PADDLEBOARDING
- Paddleboards
- Paddleboard Paddles
- CLOTHING AND PFDs
- Dry Suits
- Paddling Footwear
- Paddling Gloves
- Paddling Jackets
- PFDs
- Rashguards
- Wetsuits
- All Paddling Clothing
-
Snowsports
- DOWNHILL SKIING
- Downhill Skis
- Downhill Ski Bindings
- Downhill Ski Boots
- Ski Bags
- Ski Goggles
- Ski Helmets
- Ski Packs
- Downhill Ski Poles
- Men's Downhill Ski Clothing
- Women's Downhill Ski Clothing
- Gloves, Hats and Socks
- All Downhill Skiing
- XC AND BACKCOUNTRY
- Cross-Country Skiing
- Backcountry Skiing
- Nordic Touring
- Metal-Edge Touring
- Race/Performance Skiing
- Cross-Country Ski Tuning
- Cross-Country Ski Waxes
- Men's XC Clothing
- Women's XC Clothing
- Kids' XC Ski Gear
- All Cross-Country
- All Tele/Randonee
- SNOWBOARDING
- Snowboards
- Snowboard Bags
- Snowboard Bindings
- Snowboard Boots
- Snowboard Goggles
- Snowboard Helmets
- Snowboard Packs
- Stomp Pads
- Men's Snowboard Clothing
- Women's Snowboard Clothing
- Gloves, Hats and Socks
- All Snowboarding
-
Travel
- LUGGAGE
- Carry-On Luggage
- Travel Packs
- Wheeled Backpacks
- Wheeled Duffels
- Wheeled Luggage
- Kids' Luggage
- Bike Travel Cases
- Ski Bags
- All Luggage
- DAY BAGS
- Camera Bags
- Daypacks
- Duffel Bags
- Handbags
- Laptop Bags
- Messenger Bags
- Shoulder Bags
- Travel Totes
- All Day Bags
- PACKING
- Luggage Locks
- Luggage Tags
- Organizers
- Packing Cubes
- Packing Folders
- Pouches
- Electronics Cases
- Toiletry Kits
- All Packing
-
Men
- MEN'S JACKETS
- Casual Jackets
- Down Jackets
- Fleece Jackets
- Insulated Jackets
- Rain Jackets
- Running Jackets
- Wind Shells
- Ski Jackets
- Snowboard Jackets
- Soft Shell Jackets
- All Men's Jackets
- MEN'S CLOTHING
- Pants
- Shirts
- Shorts
- Sweaters
- Swimming
- Underwear
- Vests
- Footwear
- Tall Clothing
- All Men's Clothing
- MEN'S ACCESSORIES
- Balaclavas
- Bandanas
- Belts
- Gaiters
- Gloves and Mittens
- Hats
- Headwear
- Socks
- Sunglasses
- Watches
- All Accessories
-
Women
- WOMEN'S JACKETS
- Casual Jackets
- Down Jackets
- Fleece Jackets
- Insulated Jackets
- Rain Jackets
- Running Jackets
- Wind Shells
- Ski Jackets
- Snowboard Jackets
- Soft Shell Jackets
- All Women's Jackets
- WOMEN'S CLOTHING
- Footwear
- Pants
- Shirts
- Shorts
- Skirts and Dresses
- Sweaters
- Swimming
- Underwear
- Vests
- Petite Clothing
- Plus Sizes
- All Women's Clothing
- WOMEN'S ACCESSORIES
- Belts
- Gaiters
- Gloves and Mittens
- Hats
- Headwear
- Scarves
- Socks
- Sports Bras
- Sunglasses
- Watches
- All Accessories
-
Kids
- KIDS' SHOPS
- Boys' Clothing
- Girls' Clothing
- Infant & Toddler Clothing
- Kids' Outerwear
- Kids' Shoes
- Kids' Ski Clothing
- Kids' Snowboard Clothing
- Eco-Conscious
- All Kids'
- ACCESSORIES
- Hats
- Gloves and Mittens
- Socks
- Sunglasses
- Toys
- Underwear
- Water Bottles
- All Kids' Accessories
-
Footwear
- MEN'S FOOTWEAR
- Men's Boots
- Men's Sandals
- Men's Shoes
- Men's Slippers
- Men's Wide Sizes
- Men's Socks
- WOMEN'S FOOTWEAR
- Women's Boots
- Women's Sandals
- Women's Shoes
- Women's Slippers
- Women's Narrow Sizes
- Women's Wide Sizes
- Women's Socks
- KIDS' FOOTWEAR
- Kids' Boots
- Kids' Sandals
- Kids' Shoes
- Kids' Slippers
- Kids' Socks
- FOOTWEAR ACCESSORIES
- Gaiters
- Insoles
- Laces
- Treatments
- Winter Traction
- Brands
-
All
- Backcountry Skiing Shop
- Backpacks
- Binoculars
- Bikes
- Books and Maps
- Camping and Hiking
- Car Racks
- Climbing
- Cross-Country Skiing
- Cycling
- Dog Gear
- Downhill Skiing Shop
- Electronics
- Fitness
- Gift Cards
- GPS
- Hammocks
- Helmet Cams
- Jackets
- Kids'
- Luggage and Day Bags
- Made in the USA
- Men's Clothing
- Men's Shoes and Boots
- Outdoor Lifestyle
- Paddling
- Running
- Sale & Clearance
- Sleeping Bags
- Snowboarding Shop
- Snowshoeing Shop
- Snowsports
- Strollers
- Deals
REI Anniversary Sale May 17–27. Plus, members SAVE 20% on 1 full-price item with coupon code ANNV13. Details
- REI Gift Cards
- Buy now!
- Check your REI gift card balance
- REI Membership
- REI member benefits include an annual refund (typically 10% on eligible purchases).
- Join REI today!
- Sign up for REI Gearmail®
- and get 15% off selected items!
- Store Locator
- Locate an REI store near you.
-
- Company Info
- About REI
- Jobs at REI
- 100% Satisfaction Guarantee
- Corporate & Group Sales
- Privacy Policy
- Terms of Use
- Site Rules
- California Transparency in Supply Chains Act - REI's Disclosure
- REI Membership
- Become an REI Member
- Member Help
- Find Membership Number
- Dividend Lookup
- Apply for an REI Visa® Card
- Manage Your REI Visa® Card
- We Care
- Stewardship
- Volunteer
- Eco-Conscious Gear
- Expert Outdoor Advice
- Expert Advice Articles
- Outdoor Videos
- REI Outdoor School
- Store Events
- Online Affiliate Program
- Become an REI Affiliate
- Gift Registry
- Shop All Brands
- Shop Our Catalogs
- Shop All Categories