Merrell Moab 3 Thermo Tall WP 400g Insulated Boots Review

Merrell’s Moab 3 Thermo Tall WP winter boots are insulated with 400g Primaloft Gold Eco Series synthetic insulation making them suitable for cold-weather hiking. While Merrell does not cite a temperature rating, these boots are comparable to other 400g insulated boots on the market that have a rating of -40F. Despite their name, these boots are not particularly “tall” and only measure 7.5 inches in height from the bottom of the sole to the top of the laces, making them feel more like regular hiking boots and not the truly tall insulated winter boots offered by other manufacturers. There are advantages and disadvantages to that height difference as I explain below.

Specs at a Glance

• Type: insulated boots (sole to cuff height 7.5″)
• Gender: men’s (women’s sizes are NOT available)
• Insulation: 400g Primaloft Gold Eco synthetic insulation
• Outsole: Vibram IceTrek soles
• Waterproof/Breathable: Yes
• Wide Sizes: Not available in a Wide
• Material: Leather and textile
• Drop: 11.5 mm
• Lug Depth: 5.0 mm

Not that Tall at All

Most 400g insulated winter hiking boots are tall reaching well up the calf to capture more body heat in order to keep your feet warmer. Not so with the Merrell Moab 3 Thermo Tall WP. At 7.5″ in height from the heel to the top of the laces, these boots are not particularly tall and are sized more like regular hiking boots. That’s advantageous because  you don’t have to change your stride as you do with taller winter boots that have less range of motion in the ankles. This makes hiking and snowshoeing with them more natural than a taller boot and puts a lot less stress on your hip flexors. But as a point of comparison, the 200g insulated Merrell Moab Speed Thermo Mid that I reviewed recently is only a half-inch shorter in height, so at 7.5″ the Moab 3 Thermo isn’t really tall at a all.

Waterproofing

The Moab 3 Thermo is made with a waterproof/breathable membrane to prevent water from seeping through the leather and textile exterior. As far as breathability goes, don’t get your hopes up. Foot sweat makes my socks damp when I’ve go winter hiking with these boots. That’s not surprising. I’ve never owned a pair of waterproof/breathable winter hiking boots where that wasn’t the case.

Construction

These boots have a textile and leather upper with good front toe-kick protection. But the top of the toe box behind the front kick is a bit soft and does compress if you put on microspikes that have a tight elastomer harness. The toe box fit also runs narrow so you may experience some lack of room depending on how much toe box width you prefer. I find it cramped.

The tongue is heavily padded and covered in fleece for added comfort and warmth. There is a gaiter ring at the base of the tongue to hook your gaiters too and the tongue is bellowed along the sides to prevent moisture from leaking inside. The top cuff is fleece lined with a rigid leather heel counter for stability and protection. There is NOT a ridge on the back of the heel to prevent a rear snowshoe strap from slipping off, however, which is quite a nice feature on some 400g insulated boots including the Oboz Bridger 10″/9″.

The Moab 3 Thermo Tall WP has a nylon arch shank which is very lightweight but supporting. It’s useful on a softer sole boot like this because it stiffens the sole and diminishes the load on you arches, calves, and knees. These boots include a pretty decent wool covered insole with a secure heel cup and extra cushioning under the heel and ball of the foot as well.

Vibram IceTrek Outsoles

The Moab 3 Thermo Tall WP has Vibram IceTrek outsoles with really beefy 5 mm lugs.  The outsoles are soft and grippy with a distinct arch which is good to capture a gaiter strap.  They’re made with a rubber compound designed for low to medium temperatures with multidirectional lugs that are designed to provide traction when hiking across ice or snow-covered terrain.

Vibram IceTrek soles are engineered to provide extra grip and traction on icy surfaces, or that’s what Vibram’s marketing claims. I haven’t found that to be the case because I slide around anyway when I hit icy patches in these boots, or any other boots for that matter  It’s a moot point anyway because hikers wear microspikes or crampons when they need extra traction on icy terrain and the soles never touch the ground.

Recommended winter hiking boots

Recommendation

Merrell’s Moab 3 Thermo Tall WP winter boots are insulated with 400g Primaloft Gold Eco Series synthetic insulation making them suitable for cold-weather hiking down to -40F degrees. They’re warm and waterproof but fit more like regular hiking boots and not the taller calf-high 400g insulated winter hiking boots sold by other brands. Made with a combination of leather and textile, they’re lined with a waterproof/breathable membrane to keep your feet dry with a soft fleece ankle cuff and tongue that makes them very comfortable to wear. While they are wearable out of the box without breaking them in, the sizing does run noticeably narrow and wide sizes are not available. If that’s not an issue, they’re a good choice if you want better calf ventilation and a boot that provides more ankle range of motion.

Disclosure: The author owns these shoes.

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