This is Exponential Deviation Bands. It is a price band indicator based on exponential deviation rather than the more traditional standard deviation, as you find in the well-known Bollinger Bands
calculation. As compared to standard deviation bands, exponential deviation bands apply more weight to recent data and generate fewer breakouts. There fore it is a much better tool to identifying trends.
One strategy on the daily can be
- Buy next bar if closing price crosses below the lower bands
- Sell if price is equal to the current value of the upper bands