Jeffrey Sei has 2 recorded races from Lancaster, CA, US.
| Date | Race | Distance | Time | Overall |
|---|---|---|---|---|
| 2026-05-31 | 2026 Rock 'n' Roll San Diego Half Marathon | Half Marathon | 2:42:50 | 13331 |
| 2025-06-01 | 2025 Rock 'n' Roll San Diego Half Marathon | Half Marathon | 2:29:40 | 10861 |