Raymarine Micronet Race Master
T070 Race Master.
The ultimate tactical race compass and wind shift indicator. Its two-tier display shows your heading, how far you're above or below the mean course, and how much you're being headed or lifted. It will enable you to quickly and easily establish 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.