Al Brooks describes two patterns that I use very often in my strategy for trading. Double bottom bull flag is pause or flag during the development of the bull trend, in which there are two spikes down to almost the same level, and then the bull trend resumes.

Double top bear flag is a pause or flag during the development of a bear trend, in which there are two spikes up to almost the same level, and then the bear trend resumes.

These two patterns are actually my best set-up for position opening. They show the price action confirming that probably large orders are filled in the direction of the trend.