All mariners need a comprehensive knowledge of the buoyage rules and should be able instantly to identify a mark at first sight. These Flash Cards show different buoys and navigational marks in colour, with the meaning and position, together with the light characteristics on the back of the card. Cardinal marks and IALA Regions A & B are featured as well as the more recent preferred channel buoys. There are over 50 cards in the set. Presented in a clear plastic hard case.