AS568-278 O-Ring
Inside diameter 11.984″
Cross-section 0.139″
Outside diameter 12.262″
Metric (ID × CS) 304.39 × 3.53 mm
OD is derived: ID + 2 × CS = 11.984″ + 2 × 0.139″ = 12.262″.
Neighboring sizes (CS 0.139″ series)
| Dash | ID | OD | ID mm | vs -278 |
|---|---|---|---|---|
| -276 | 10.984″ | 11.262″ | 278.99 | ID −1.000″ |
| -277 | 11.484″ | 11.762″ | 291.69 | ID −0.500″ |
| -278 | 11.984″ | 12.262″ | 304.39 | — |
| -279 | 12.984″ | 13.262″ | 329.79 | ID +1.000″ |
| -280 | 13.984″ | 14.262″ | 355.19 | ID +2.000″ |