Price Headley\'s Acceleration Bands serve as a trading envelope that factor in a stock\'s typical volatility over standard settings of 20 or 80 bars. They can be used across any time frame, though Headley prefers to use them most across weekly and monthly timeframes as breakout indicators outside these bands, while using the shorter time frames to define likely support and resistance levels at the lower and upper Acceleration Bands. Acceleration Bands are plotted around a simple moving average as the midpoint, and the upper and lower bands are of equal distance from this midpoint.