The North Face ThermoBall Traction Mules V Review — Are They Worth It?
A puffer jacket for your feet.
The North Face ThermoBall Traction Mules V in black—my go-to camp shoes for cold mornings and van life
That’s the simplest way to describe the The North Face ThermoBall Traction Mules V —, and honestly, it’s why I love them.
I don’t love most slippers. They’re either too flimsy to wear outside, too bulky to pack, or so “indoor-only” that they feel pointless on a road trip.
I had been eyeing these for a while as a must-have for camping — whether in a tent, a car, or a van. They felt versatile. So I finally walked into the REI in Longmont, Colorado, and bought them.
After wearing the ThermoBall Traction Mules around camp, on cold van mornings, and at home during winter, I can confidently answer the question people are searching for:
Yes — they’re worth it if you want warmth, comfort, and real traction in one simple slip-on.
What Are the ThermoBall Traction Mules V?
These are insulated, fleece-lined slip-on mules with a rubber outsole — essentially a lightweight insulated camp shoe.
They feature:
ThermoBall™ Eco insulation
Soft fleece interior
Recycled ripstop upper
Durable rubber traction outsole
Collapsible heel for easy on and off
They’re designed for base camp comfort, but they’ve become my go-to for much more than that.
I wear them walking Chloe, taking the trash out, stepping outside around the van, and doing quick chores when I don’t feel like lacing up real shoes. That’s what makes them different from basic house slippers — they’re comfortable, but they’re also functional.
Warmth & Comfort — Do They Actually Keep Your Feet Warm?
Yes.
The ThermoBall insulation holds warmth without feeling heavy or bulky. They warm up quickly once you put them on, and the fleece lining adds that soft, cozy feel that makes them comfortable enough for all-day wear.
They aren’t built for deep snow or wet winter storms. But for:
Cold van mornings
Post-hike evenings at camp
Shoulder-season travel
Cabin weekends
Chilly floors at home
They do exactly what I want them to do.
If you struggle with cold feet, especially during fall and winter, these make a noticeable difference.
What Is ThermoBall?
Before buying these, I honestly did not know what ThermoBall meant.
The North Face uses ThermoBall™ Eco insulation, which is made from recycled material and designed to mimic the warmth of down. Instead of one flat layer of insulation, it uses small round fiber clusters—almost like tiny balls packed together—that trap heat in small air pockets.
That’s part of why these feel so warm without feeling bulky.
Another benefit is moisture. Unlike traditional down, ThermoBall is designed to keep insulating even if it gets damp, which makes a lot of sense for camp life, cold mornings around the van, or stepping outside when there’s dew on the ground.
After learning how it works, the warmth in these made a lot more sense.
Are the ThermoBall Traction Mules Worth It?
This is the real question.
If you’re looking for a basic house slipper, there are cheaper options.
If you’re looking for a winter boot, these aren’t that.
But if you want a warm slipper you can actually step outside in — without changing shoes — this is where they shine.
The traction outsole changes everything.
You can:
Walk to the picnic table
Step out of the van
Grab firewood
Check the mail
Run a quick errand
Without swapping footwear.
That versatility is what makes them worth it.
They’re just easy.
Fit & Sizing
The fit is roomy and comfortable right away — there’s no break-in period.
If you wear thicker socks, the roominess works in your favor. If you prefer a snug fit, you may want to size down. Otherwise, true to size works well.
The collapsible heel makes them easy to slide on quickly — which matters more than you think on a cold morning.
Traction & Durability
This is where they separate themselves from typical slippers.
The rubber outsole has real grip — not hiking boot grip, but enough for gravel, pavement, campgrounds, and decks.
They don’t feel disposable. The ripstop upper holds its shape, and the insulation maintains loft.
They’re lightweight and easy to pack in a van or travel bag without taking up unnecessary space.
When They Make the Most Sense
These are ideal for:
Van life mornings
Winter travel
Shoulder-season camping
Post-ski or après days
Cabin stays
Sitting outside in a chair on a chilly evening
They bridge the gap between house slipper and outdoor camp shoe.
It’s warm. It’s comfortable. It works.
Pros
Warm without bulk
Soft fleece lining
Real traction outsole
Lightweight and packable
Easy on and off
Cons
Not waterproof
Not designed for deep winter snow
Slightly roomy fit for some
Final Take
If you’re looking for something that’s just a house slipper, there are cheaper options.
If you want something that feels like a puffer jacket for your feet — warm, comfortable, and functional enough for real use — the ThermoBall Traction Mules V earn their place.
They’re simple. They’re warm. They work.
Michele Underwood writes Overland Girl, where she shares the gear she uses on real trips—from the Northwoods of Wisconsin to desert rides in the West. She values quality and craftsmanship and believes in buying less, but buying better. The gear she recommends is gear she uses herself.Some links on Overland Girl may be affiliate links. If you purchase through them, Michele may earn a small commission at no extra cost to you.