The indicator draws boxes when close to close returns are positive for at least a specified number of bars. The last bar is only included in the box (if positive) after the market is closed, to avoid false positives.
The standard use (by William O'Neil) is on weekly charts, using at least five consecutive up bars to define a box (indicating strong institutional buying activity).
Options:
* minimum number of up bars to form a box
* include flat bars (zero return) in the up count
* add labels to top and bottom box levels, as shown in the sample chart