## Conquer the pavement with the adidas UltraBoost 21 in sleek Crew Navy (FY0350). These performance running shoes combine supreme comfort with energetic boost midsole cushioning for an unparalleled stride. The Primeknit+ upper hugs your foot securely while providing breathability, making every run effortless. Experience the future of running; experience UltraBoost.
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| U.S. Size | U.K. Size | EU Size | Foot Length (Inches) | Foot Length (cm) |
|---|---|---|---|---|
| 6 | 5.5 | 39 | 9.25 | 23.5 |
| 6.5 | 6 | 39.5 | 9.5 | 24.1 |
| 7 | 6.5 | 40 | 9.625 | 24.4 |
| 7.5 | 7 | 40.5 | 9.75 | 24.8 |
| 8 | 7.5 | 41 | 9.9375 | 25.4 |
| 8.5 | 8 | 42 | 10.125 | 25.7 |
| 9 | 8.5 | 42.5 | 10.25 | 26.0 |
| 9.5 | 9 | 43 | 10.4375 | 26.7 |
| 10 | 9.5 | 44 | 10.5625 | 27.0 |
| 10.5 | 10 | 44.5 | 10.75 | 27.3 |
| 11 | 10.5 | 45 | 10.9375 | 27.9 |
| 11.5 | 11 | 45.5 | 11.125 | 28.3 |
| 12 | 11.5 | 46 | 11.25 | 28.6 |
| 13 | 12.5 | 47 | 11.5625 | 29.4 |
