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

Kosei

MMSI 431759000

Not yet on Master's Mate

Flag

JPN

Length

73 m

IMO

9830719

AIS reports

Registered in Japan, Kosei is a 73-metre boat. She's listed under MMSI 431759000, IMO 9830719. Claim Kosei free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.

Free forever · No credit card

Is Kosei 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

Wherever Kosei roams, you're never out there alone.

Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.

Free with your claim

The most powerful cruising platform ever built — yours, free.

Joining the Safety Initiative Network doesn't just put Kosei 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 Kosei and switch it all on

Free to join · nothing to install to start · cancel anytime

Claim free → unlock everything

About Kosei

What kind of vessel is Kosei?

Kosei is a vessel flagged to Japan.

What is Kosei's MMSI?

Kosei's MMSI is 431759000. IMO 9830719.

How big is Kosei?

Kosei is about 73 m long.

Is Kosei on the Master's Mate Safety Initiative Network?

Not yet. If Kosei is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).