This indicator is a modified form of Bollinger Bands.
It works in a similar way like BB does. If you take a look at the "line" chart, you will clearly see, that a close outside these bands is very unlikely and works very well as a rejection line for the chart.
Since, the chart is likely to get rejected at the bands those have been indicated red at the top and green at the bottom.
The use is very simple, add it to your chart and there is nothing more to modify or change.
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