MMSI 366398130 · Call sign WBQ6710
Not yet on Master's MateGRAND SLAM is an American boat. On the registers she's MMSI 366398130, call sign WBQ6710. Sign GRAND SLAM up free to the Master's Mate Safety Initiative Network and join a fleet that looks after its own.
Your free claim unlocks the most powerful cruising platform ever built — anchor watch, worldwide charts, live AIS, weather routing, and a network of cruisers watching each other’s backs.
Claim this boat — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Joining the Safety Initiative Network doesn't just put GRAND SLAM on the map. It hands you the full bridge:
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