MMSI 366587010 · Call sign WCG5423
Not yet on Master's MateFlying the American flag, ROCK BOTTOM III is a boat. On the registers she's MMSI 366587010, call sign WCG5423. The Master's Mate Safety Initiative Network welcomes ROCK BOTTOM III — free to join, cruiser-run, and always on watch.
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 ROCK BOTTOM III on the map. It hands you the full bridge:
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