A box-line intersection combined with Almost Locked Sets (ALS) from remaining cells; powerful cross-eliminations result.
The cells at a box-line intersection contain N+K candidates for N cells. The K extra candidates must be distributed between an ALS in the remaining box cells and an ALS in the remaining line cells. This locking creates cross-eliminations in both directions.
One of the hardest techniques to spot and understand.
Visual board example for this technique is not available yet.