Please note that the S1 has a standard width. If you require a wider toe box, we recommend choosing the R1 or P1 instead.
We offer free shipping on all orders and the estimated delivery time is 2-5 working days in the US.
We offer free return or exchange on unworn, unwashed shoes within 30 days.
APMA Seal of Acceptance
This product received the American Podiatric Medical Association (APMA) Seal of Acceptance, awarded to products found by the Association to promote good foot health.
Men's
| USA | 7 | 7.5 | 8 | 8.5 | 9 | 9.5 | 10 | 10.5 | 11 | 11.5 | 12 | 12.5 | 13 | 14 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| EUR | 40 | 40.5 | 41 | 42 | 42.5 | 43 | 44 | 44.5 | 45 | 46 | 47 | 47.5 | 48 | 49 |
| UK | 6 | 6.5 | 7 | 7.5 | 8 | 8.5 | 9 | 9.5 | 10 | 10.5 | 11 | 11.5 | 12 | 13 |
| CM SIZE | 25 | 25.5 | 26 | 26.5 | 27 | 27.5 | 28 | 28.5 | 29 | 29.5 | 30 | 30.5 | 31 | 32 |
Women's
| USA | 5 | 5.5 | 6 | 6.5 | 7 | 7.5 | 8 | 8.5 | 9 | 9.5 | 10 | 10.5 | 11 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| EUR | 35.5 | 36 | 36.5 | 37.5 | 38 | 38.5 | 39 | 40 | 40.5 | 41 | 42 | 42.5 | 43 |
| UK | 3 | 3.5 | 4 | 4.5 | 5 | 5.5 | 6 | 6.5 | 7 | 7.5 | 8 | 8.5 | 9 |
| CM SIZE | 22 | 22.5 | 23 | 23.5 | 24 | 24.5 | 25 | 25.5 | 26 | 26.5 | 27 | 27.5 | 28 |
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Size Measuring Guide
A perfect fit for your ultra-marathon running shoes is important for comfort and performance. Follow these tips to measure your foot size at home:
General Tips:
- Measure your feet at the end of the day as they're at their largest due to swelling.
- In between sizes? One foot is bigger than the other? Take the larger size.
- It's best to measure every year. Your size could change over time.
What You'll Need:
- A piece of paper larger than your foot,
- A pen or pencil,
- A ruler or measuring tape,
- Socks of the thickness you'll wear with the shoes.
Steps:
- Stand on the paper in the socks you'll wear with the shoes.
- Use the pen or pencil to mark the end of your longest toe and the back of your heel. It's important to measure both feet as their size can vary.
- Match your measurements to our size chart to find the best fit. If you're between sizes, we suggest choosing the larger size for better comfort.
S1gned, Sealed, Delivered
Cushioning You Can Rely On
Lighten Up and Find Your Pace
Flow Like Water
Our engineered Jacquard mesh combines exceptional softness with a hardwearing, tailored fit. And by utilizing 100 percent recycled yarn, it's more sustainable, so it plays a part in creating a greener planet.
Details You'll Love
