KEEN Revel IV High Polar Boots Review
KEEN’s Revel IV High Polar Boots are insulated waterproof/breathable winter hiking boots rated to -40F/-40C. Available for both men and women, these boots come up to mid-calf for maximum heat retention and feature metal lacing hardware for maximum durability, a gaiter ring above the toes, and a ridged heel counter that helps keep snowshoes securely fastened. Lined with fleece, the Revel IV’s are exceptionally comfortable for all-day comfort. Sizing runs about one-quarter to half of a size small, so I’d size up and plan on wearing a slightly heavier sock. Wide sizes are not available and while the toe box is roomy, it’s not as high volume as many of KEEN’s other mids or boots.
Specs at a Glance
- Temperature Rating: -40F/-40C
- Height: Mid-calf
- Waterproof/Breathable: Yes
- Gender: Men’s (size 7-15); Women’s (size 5-12)
- Sole: 5mm lugs
- Sizing: Runs one-quarter to a half-size small.
- Insole: Felted thermal insole
- Weight: 3 lbs 8 oz/pr (size 11 men’s)
I’ve always found KEEN winter hiking boots to be very warm and the Revel IV is no exception. This is the kind of boot you want for long winter hikes when your trips start before the sun comes up and ends after it goes down.
With a temperature rating of -40F/-40C, the Revel IV is insulated with environmentally friendly charcoal and bamboo, instead of the usual Thinsulate used by most other winter boot manufacturers. The upper cuff and tongue are covered with fleece while the exterior is covered in leather with ballistic nylon in high flex areas.

The Revel IV has a large front toe kick for toe protection and a reinforced heel counter to lock your heel in place and prevent pronation. Ridges on the back of the heel help keep snowshoe, crampon, or microspike straps secure which is a real plus for more technical winter hikes from traction aids are required. However, the boots have a very shallow mid-sole arch which can prove challenging if you wear gaiters with a thick stirrup strap, like OR Crocodiles, as it can cause abrasion if you walk on surfaces that are not covered with snow and ice.
KEEN provides a thermal insole with the Revel IV Polar Boot, which is covered in felt for warmth but does not have a reflective aluminum coating. When worn, the boots have a pretty low arch, so I wear mine with Superfeet’s merinoGrey insoles which are wool-covered for warmth but have a much more aggressive arch to protect against plantar fasciitis.

Traction is more than adequate and the boots have deep 5mm multi-directional lugs to grip snow and ice. The edges of the soles are also quite stiff, which makes them good for scrambling over rock ledges when you need a sole that won’t collapse on a narrow foothold.
There’s minimal time to break-in the Revel IV boots which are soft and pliant out or the box. KEEN also sells an “over-the-ankle” mid-sized versions of the Revel IV High Polar Boot called the Revel IV Polar Boot (note the missing “High”) that is rated to -25F, if you need less insulation or prefer a mid-sized height.

Comparable 400g (-40F/-40C) Insulated Winter Hiking Boots
Recommendation
KEEN’s Revel IV High Polar Insulated Boots are are really good for men and women who want or need warm winter hiking footwear. Rated to -40F/-40C, their high mid-calf height helps lock in warmth while a fleece-lined collar and tongue provide both comfort and additional warmth. Their thick soles provide excellent insulation from the cold ground while durable metal hardware ensures trouble-free use and long life. The sizing runs slightly small, so consider sizing up a half size. Amazingly, these boots are wearable out of the box and require virtually no break-in period.
Disclosure: The author purchased this product.
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Last updated: 2020-11-23 22:24:42
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