Bollinger Bands %B is essentially BB Range it is an indicator derived from the standard Bollinger Bands. Bollinger Bands are a volatility indicator that creates a band of three lines which are plotted on the screen.
Bollinger Bands %B works the same as other momentum oscillators, it is best to look for short-term oversold in this case a volatility imbalance between upper and lower volatility. You are looking for values that are near 0 or negative.
Compared to other momentum Oscillators the %B is slightly less responsive than CCI but it does provide more signals than RSI / STOCH and STOCHRSI.