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

Thru & Thru

MMSI 367778080 · Call sign WDJ4478

Not yet on Master's Mate

Flag

USA

Call sign

WDJ4478

Official No.

1275081

AIS reports

Thru & Thru is a vessel, wearing American colours. On AIS she appears as MMSI 367778080, call sign WDJ4478. Claim Thru & Thru free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.

Free forever · No credit card

Is Thru & Thru 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 Thru & Thru 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 Thru & Thru 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 Thru & Thru and switch it all on

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

Claim free → unlock everything

About Thru & Thru

What kind of vessel is Thru & Thru?

Thru & Thru is a vessel flagged to United States of America.

What is Thru & Thru's MMSI?

Thru & Thru's MMSI is 367778080. Call sign WDJ4478.

Is Thru & Thru on the Master's Mate Safety Initiative Network?

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