Its two-tier display shows your heading, how far you are above or below the mean course, and how much you are being headed or lifted. It will enable you to establish quickly and easily which is the favoured end of the start line, and will help you sail the shortest distance to the windward mark. Downwind, you can see how far off dead downwind you are, and when you should gybe for optimal VMG. Data Displayed: Compass Heading, Wind Shift Indicator, Line Bias, Race Timer. 100% Solar powered.