Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Vessel
SEIUNMARU NO.28
Japan · last seen 39°N 142°E · Jun 2026 · MMSI 431000929
Not yet on Master's MateFlag
JPNFirst reported
Jun 2026
Last reported
Jun 2026
AIS reports
20
Flying the Japanese flag, SEIUNMARU NO.28 is a craft. On AIS she shows as MMSI 431000929. SEIUNMARU NO.28 is invited to the free Master's Mate Safety Initiative Network, where cruisers keep each other safe.
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Is SEIUNMARU NO.28 your boat?
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
Last known position · Jun 4, 2026
Position
39.0527° N, 141.7275° E
Crossing the Sea of Japan? You're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
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The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put SEIUNMARU NO.28 on the map. It hands you the full bridge:
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim SEIUNMARU NO.28 and switch it all on
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About SEIUNMARU NO.28
What kind of vessel is SEIUNMARU NO.28?
SEIUNMARU NO.28 is a vessel flagged to Japan.
Where was SEIUNMARU NO.28 last seen?
SEIUNMARU NO.28 was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is SEIUNMARU NO.28's MMSI?
SEIUNMARU NO.28's MMSI is 431000929.
Is SEIUNMARU NO.28 on the Master's Mate Safety Initiative Network?
Not yet. If SEIUNMARU NO.28 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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