Stable, cushioned and built to offer a smooth, robust ride in the longest trail races, the M1 is optimized for the mountains. It features our next-gen JETCELL midsole to deliver unmatched energy return, and a full-coverage outsole with a trio of Vibram technologies for predictable grip in extreme situations.
Key Features
- Next-gen JETCELL midsole foam delivers our highest energy return and consistent performance with twice the material strength of PEBA.
- Full coverage Vibram Megagrip, Litebase, and Traction Lug technology.
- TUNEDFIT Dual Lacing System for separate lace adjustment.
- Wider base and higher sidewalls enhance stability during long runs.
- Supercritical foam insole for enhanced energy return and comfort.
Best For
Long-distance trail races
Weight
9.7 oz / 275 g
Drop (Stack Height)
4 mm (Heel 38 mm, Forefoot 34 mm)
Midsole
JETCELL™
Outsole
4 mm lugs
Vibram® Megagrip, Litebase, and Traction Lug
Lacing
TUNEDFIT™ Dual Lacing System
Upper
TPEE-blended yarns
Sizing
| 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 |
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.
