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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.
Cargo
SEIJU MARU
MMSI 431000848 · Call sign JD2871
Not yet on Master's MateType
Cargo
Flag
JPNLength
83 m
Beam
13 m
Draft
4.2 m
Call sign
JD2871
IMO
9523354
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
68
SEIJU MARU, a Japanese freighter, measures 83 metres on deck. Below, she has a beam of 13 m and a draft of 4.2 m. She broadcasts as MMSI 431000848, call sign JD2871, IMO 9523354. SEIJU MARU belongs on the Master's Mate Safety Initiative Network, a free safety net shared by boats the world over.
Free forever · No credit card · for commercial operators
Eyes on SEIJU MARU, around the clock.
Real-time AIS, full systems telemetry, distress alerting and worldwide charts — your hull on one dashboard, from anywhere.
Put her on the dashboard — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Last known position · Jun 3, 2026
Position
34.2574° N, 135.0563° E
Transiting the Sea of Japan? You're never out there alone.
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Joining the Safety Initiative Network doesn't just put SEIJU MARU on the map. It hands you the full bridge:
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
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.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim SEIJU MARU and switch it all on
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About SEIJU MARU
What kind of vessel is SEIJU MARU?
SEIJU MARU is a Cargo flagged to Japan.
Where was SEIJU MARU last seen?
SEIJU MARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is SEIJU MARU's MMSI?
SEIJU MARU's MMSI is 431000848. Call sign JD2871. IMO 9523354.
How big is SEIJU MARU?
SEIJU MARU is about 83 m long, 13 m on the beam, drawing 4.2 m.
Is SEIJU MARU on the Master's Mate Safety Initiative Network?
Not yet. If SEIJU MARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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