The Opening Bell Marker indicator is designed to assist traders by marking the 09:30 AM Eastern Time (ET) opening of the U.S. stock market with a red dashed vertical line on the chart. This feature is particularly useful for back testing strategies around market open, providing a visual reference point for the start of regular trading hours. The indicator automatically adjusts to display the line at 09:30 ET, helping traders spot key moments and potential setups during market open.