Two bivalue cells with the same candidates are connected via a conjugate pair; their common digit is eliminated from cells seeing both.
Two cells share the same two candidates {X,Z}. A conjugate pair of digit X connects them: if one cell takes X, the bridge forces the other cell to take Z, and vice versa. Either way, Z appears in one of the two endpoint cells — so any cell seeing both can have Z eliminated.
| 8 | 4 | 9 | 3 | 5 | 1 | 7 | 6 | 2 |
| 1 | 2 | 3 | 4679 | 479 | 4679 | 49 | 5 | 8 |
| 5 | 6 | 7 | 2 | 49 | 8 | 1 | 3 | 49 |
23 | 5 | 1 | 47 | 347 | 247 | 8 | 9 | 6 |
| 7 | 9 | 4 | 8 | 6 | 5 | 2 | 1 | 3 |
23 | 8 | 6 | 1 | 39 | 29 | 5 | 4 | 7 |
| 4 | 3 | 2 | 5 | 8 | 69 | 69 | 7 | 1 |
| 6 | 1 | 5 | 479 | 2 | 479 | 3 | 8 | 49 |
| 9 | 7 | 8 | 46 | 1 | 3 | 46 | 2 | 5 |
This 9×9 puzzle is solver-verified to require this technique on its solution path.