Made for trail running, the Primus Trail Knit FG is also excellent for fastpacking and hiking. Its low profile and versatility also makes it a popular choice of outdoor lovers wherever they tread. A knit upper and sock bring flexibility and protection. A quick-lace system means easy adjustments. And a thin Firm Ground sole balances barefoot sensation with grip, feeling fast on varied hardpack terrain, building natural strength with every step.
| Weight | Approx. 400g (size dependent) |
| Heel-to-Toe Drop | 0mm |
| Stack Height | 3mm base + 2.5mm tread depth |
| Midsole | No traditional midsole for maximum flexibility and natural movement |
| Outsole | Firm Ground outsole with 3mm base and 2.5mm tread depth for grip, traction and ground connection across varied hardpack terrain |
| Upper | Vamp knit upper made from 81% RPET, 10% Nylon Hotmelt and 9% Elastane with no-sew TPU overlays for added durability |
| Lining | Microfibre lining made from 40% polyester and 60% polyurethane |
| Insole | Removable Ortholite® insole with RPET components |
| Closure | Quick-lace system with toggle adjustment for easy fit changes |
| Materials | Vegan-friendly construction using recycled materials including RPET knit, TPU overlays and synthetic components |
| Best Use | Trail running, fastpacking, hiking and outdoor adventures on hardpack terrain |
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.
Made for trail running, the Primus Trail Knit FG is also excellent for fastpacking and hiking. Its low profile and versatility also makes it a popular choice of outdoor lovers wherever they tread. A knit upper and sock bring flexibility and protection. A quick-lace system means easy adjustments. And a thin Firm Ground sole balances barefoot sensation with grip, feeling fast on varied hardpack terrain, building natural strength with every step.
| Weight | Approx. 400g (size dependent) |
| Heel-to-Toe Drop | 0mm |
| Stack Height | 3mm base + 2.5mm tread depth |
| Midsole | No traditional midsole for maximum flexibility and natural movement |
| Outsole | Firm Ground outsole with 3mm base and 2.5mm tread depth for grip, traction and ground connection across varied hardpack terrain |
| Upper | Vamp knit upper made from 81% RPET, 10% Nylon Hotmelt and 9% Elastane with no-sew TPU overlays for added durability |
| Lining | Microfibre lining made from 40% polyester and 60% polyurethane |
| Insole | Removable Ortholite® insole with RPET components |
| Closure | Quick-lace system with toggle adjustment for easy fit changes |
| Materials | Vegan-friendly construction using recycled materials including RPET knit, TPU overlays and synthetic components |
| Best Use | Trail running, fastpacking, hiking and outdoor adventures on hardpack terrain |
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.