Quadrant lines get their name because they divide significant tops and bottoms into four sections (hence quad). Quad lines are three horizontal lines that are placed on a chart at 25%, 50%, and 75% points between selected minimum and maximum support points, thus dividing the chart extremes into 4 parts. They are a series of horizontal lines that divide the highest and lowest values (usually prices) into four equal sections.
If the prices move past the horizontal lines without resistance, the trend is to continue. If the prices resist moving through the horizontal lines, there is support and perhaps a trend reversal.
Quadrant Lines are primarily intended to aid in the visual inspection of price movements. They help you see the highest, lowest, and average price during a specified period.