| Personal Details | |
| Name | Sebastien Mason |
| Known As | Sebastien |
| Year of Birth | 2011 |
| Eligibility Category | Open/Male |
| Membership Details | |||
| Member Number | 1483153 | ||
| Member Status | Current | ||
| Ranked Club | Darlington SC | ||
| Country of International Representation | England | ||
| Membership Categories |
| SE Club Compete |
| Clubs & Organisations | |
| Club | Ranked |
| Darlington SC | Yes |
| Click For Personal Best | 2024 Short Course | Short Course PB | 2024 Long Course | Long Course PB |
| 50m Freestyle | 29.35 | 29.35 | 30.53 | 30.53 |
| 100m Freestyle | 1:05.17 | 1:05.17 | 1:08.32 | 1:08.32 |
| 200m Freestyle | 2:35.72 | 2:35.65 | . | 2:38.00 |
| 400m Freestyle | . | 5:30.66 | . | . |
| 800m Freestyle | . | 11:34.64 | . | . |
| 1500m Freestyle | . | . | . | . |
| 50m Breaststroke | 38.60 | 38.60 | 40.55 | 40.55 |
| 100m Breaststroke | 1:29.01 | 1:29.01 | 1:32.39 | 1:32.39 |
| 200m Breaststroke | 3:09.37 | 3:09.37 | . | 3:33.88 |
| 50m Butterfly | . | 33.39 | 31.25 | 31.25 |
| 100m Butterfly | 1:11.28 | 1:11.28 | 1:12.18 | 1:12.18 |
| 200m Butterfly | 2:48.91 | 2:48.91 | 2:51.08 | 2:51.08 |
| 50m Backstroke | 36.69 | 36.69 | . | 40.76 |
| 100m Backstroke | 1:23.42 | 1:23.42 | . | 1:43.65 |
| 200m Backstroke | . | 3:27.17 | . | . |
| 200m Individual Medley | 2:48.59 | 2:48.59 | . | 3:05.63 |
| 400m Individual Medley | . | . | . | . |
| 100m Individual Medley | 1:17.47 | 1:17.47 | . | . |
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