Vivobarefoot Primus Trail Flow Mid II Men’s Barefoot Trail Boot – Dark Shadow
The Vivobarefoot Primus Trail Flow Mid II is our lightest men’s trail boot, built for speed, agility and precision on mixed terrain. With a low-profile, zero-drop sole and flexible upper, it lets your feet move naturally while still delivering dependable grip and protection for trail running, fast hiking and everyday outdoor missions.
Why You’ll Love the Primus Trail Flow Mid II
- Ultra-light trail performance: Weighs ~219g for a fast, unrestrictive feel on the trail.
- Barefoot freedom: Wide, thin and flexible design so your feet can splay, bend and respond to the ground.
- Secure mid-height collar: Added ankle coverage and a breathable, high-cut collar for lightweight support.
- Quick-lace system: Easy on-off with a snug, reliable fit on technical terrain.
- Durable construction: Ripstop and knit upper with TPU midfoot overlay for extra protection and longevity.
Key Features
| Weight | ~219g |
| Heel-to-Toe Drop | 0mm |
| Stack Height | ~5.3mm (1.8mm base + 3.5mm outsole/lugs) |
| Midsole | No traditional midsole for maximum ground feel |
| Outsole | Trail Flow outsole with multi-terrain grip and durable lugs |
| Upper | Polyester ripstop and knit upper with TPU midfoot overlay |
| Fit | Wide, foot-shaped design for natural toe splay |
| Cushioning | Minimal |
| Support | Neutral |
| Best Use | Trail running, fast hiking, walking and outdoor adventures |
Best For
- Trail running and mixed-terrain adventures
- Fast hiking, speed hiking and light backpacking
- Runners and hikers wanting a barefoot, zero-drop feel
If you want a lightweight men’s barefoot trail boot that feels fast, nimble and connected, the Primus Trail Flow Mid II in Dark Shadow is a perfect choice.
Vivobarefoot Men’s Size Chart
Ensure your Vivobarefoot shoes fit just right. Our guide includes accurate size conversions (cm, EU, UK, US), the “rule of thumb” for toe-splay, and easy 365-day returns.
Men’s Footwear Size Guide
| Foot Length (cm) | EU | UK | US |
|---|---|---|---|
| 26.2 | 40 | 6 | 7 |
| 26.9 | 41 | 7 | 8 |
| 27.6 | 42 | 8 | 9 |
| 28.2 | 43 | 9 | 10 |
| 28.9 | 44 | 10 | 11 |
| 29.5 | 45 | 11 | 12 |
| 30.2 | 46 | 11.5 | 12.5 |
| 30.9 | 47 | 12 | 13 |
| 31.5 | 48 | 13 | 14 |
| 32.2 | 49 | 14 | 15 |
The Rule of Thumb
Vivobarefoot deliberately fits larger—your toes need room to splay naturally. If you can fit your thumb between your longest toe and the shoe’s front, you're likely wearing the right size. Over time, as toes spread, you may need to move up a size.
How to Measure Your Feet
- Stand on a hard surface with your heel against a wall.
- Mark the tip of your longest toe and measure to the wall in cm.
- Use the measurement above to choose the corresponding EU/UK/US size.
- Measure both feet and use the longer measurement.
Sizing Tips & Returns
- Vivobarefoot shoes run larger than traditional footwear—don’t worry, this supports natural toe splay.
- If you’re between sizes, we recommend sizing up for comfort rather than over-tight fit.
- Changed your mind? Return unused shoes within 365 days for a full refund or store credit—no questions asked.
Vivobarefoot Primus Trail Flow Mid II Men’s Barefoot Trail Boot – Dark Shadow
The Vivobarefoot Primus Trail Flow Mid II is our lightest men’s trail boot, built for speed, agility and precision on mixed terrain. With a low-profile, zero-drop sole and flexible upper, it lets your feet move naturally while still delivering dependable grip and protection for trail running, fast hiking and everyday outdoor missions.
Why You’ll Love the Primus Trail Flow Mid II
- Ultra-light trail performance: Weighs ~219g for a fast, unrestrictive feel on the trail.
- Barefoot freedom: Wide, thin and flexible design so your feet can splay, bend and respond to the ground.
- Secure mid-height collar: Added ankle coverage and a breathable, high-cut collar for lightweight support.
- Quick-lace system: Easy on-off with a snug, reliable fit on technical terrain.
- Durable construction: Ripstop and knit upper with TPU midfoot overlay for extra protection and longevity.
Key Features
| Weight | ~219g |
| Heel-to-Toe Drop | 0mm |
| Stack Height | ~5.3mm (1.8mm base + 3.5mm outsole/lugs) |
| Midsole | No traditional midsole for maximum ground feel |
| Outsole | Trail Flow outsole with multi-terrain grip and durable lugs |
| Upper | Polyester ripstop and knit upper with TPU midfoot overlay |
| Fit | Wide, foot-shaped design for natural toe splay |
| Cushioning | Minimal |
| Support | Neutral |
| Best Use | Trail running, fast hiking, walking and outdoor adventures |
Best For
- Trail running and mixed-terrain adventures
- Fast hiking, speed hiking and light backpacking
- Runners and hikers wanting a barefoot, zero-drop feel
If you want a lightweight men’s barefoot trail boot that feels fast, nimble and connected, the Primus Trail Flow Mid II in Dark Shadow is a perfect choice.
Vivobarefoot Men’s Size Chart
Ensure your Vivobarefoot shoes fit just right. Our guide includes accurate size conversions (cm, EU, UK, US), the “rule of thumb” for toe-splay, and easy 365-day returns.
Men’s Footwear Size Guide
| Foot Length (cm) | EU | UK | US |
|---|---|---|---|
| 26.2 | 40 | 6 | 7 |
| 26.9 | 41 | 7 | 8 |
| 27.6 | 42 | 8 | 9 |
| 28.2 | 43 | 9 | 10 |
| 28.9 | 44 | 10 | 11 |
| 29.5 | 45 | 11 | 12 |
| 30.2 | 46 | 11.5 | 12.5 |
| 30.9 | 47 | 12 | 13 |
| 31.5 | 48 | 13 | 14 |
| 32.2 | 49 | 14 | 15 |
The Rule of Thumb
Vivobarefoot deliberately fits larger—your toes need room to splay naturally. If you can fit your thumb between your longest toe and the shoe’s front, you're likely wearing the right size. Over time, as toes spread, you may need to move up a size.
How to Measure Your Feet
- Stand on a hard surface with your heel against a wall.
- Mark the tip of your longest toe and measure to the wall in cm.
- Use the measurement above to choose the corresponding EU/UK/US size.
- Measure both feet and use the longer measurement.
Sizing Tips & Returns
- Vivobarefoot shoes run larger than traditional footwear—don’t worry, this supports natural toe splay.
- If you’re between sizes, we recommend sizing up for comfort rather than over-tight fit.
- Changed your mind? Return unused shoes within 365 days for a full refund or store credit—no questions asked.
WHY GO BAREFOOT
Wearing Vivos for 6 months increases foot strength by 60%
Better Balance and Posture
Foot-shaped fit enables toes to splay supporting balance and a stable base of support.
Improved Coordination And Agility
Thin sole allows the thousands of nerve endings in each foot enabling the sensory feedback the brain needs to move with skill.
Improved Strength and Natural Movement
Flexible footwear let the muscles and tendons load and recoil, supporting stronger, more resilient feet over time.
15,000+ Reasons to Give Us a Try
At Adventureco, we stand behind every product we sell. That’s why you’re covered by our 365-Day Return Policy — with free returns within Australia.
Not the right fit? Changed your mind? No worries. Return your gear in unused condition within 365 days for a full refund or store credit — no fuss, no pressure.
Trusted for 9+ years and over 15,000 orders delivered. Shop with confidence, the adventure is guaranteed.