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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

Seisho Maru

MMSI 431100544

Not yet on Master's Mate
Flag
JPNJPN
Length
86 m
IMO
9192131
AIS reports
2

Seisho Maru is a boat hailing from Japan, 86 metres from stem to stern. On AIS she shows as MMSI 431100544, IMO 9192131. Join Seisho Maru to the Master's Mate Safety Initiative Network — free, and built by cruisers for cruisers.

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Is Seisho Maru 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.

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Wherever Seisho Maru roams, 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 Seisho Maru 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 Seisho Maru and switch it all on
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About Seisho Maru

What kind of vessel is Seisho Maru?
Seisho Maru is a vessel flagged to Japan.
What is Seisho Maru's MMSI?
Seisho Maru's MMSI is 431100544. IMO 9192131.
How big is Seisho Maru?
Seisho Maru is about 86 m long.
Is Seisho Maru on the Master's Mate Safety Initiative Network?
Not yet. If Seisho Maru is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).

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