MMSI 338130000 · Call sign WDH9963
Not yet on Master's MateDouble Skin 509A flies the American flag — a vessel. She's listed under MMSI 338130000, call sign WDH9963. Double Skin 509A belongs on the Master's Mate Safety Initiative Network, a free safety net shared by boats the world over.
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 Double Skin 509A on the map. It hands you the full bridge:
© 2026 Master’s Mate. All rights reserved.