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.
Towing Vessel
Penn No. 4
MMSI 366920960 · Call sign WDG9745
Not yet on Master's MateType
Towing Vessel
Flag
USALength
36.6 m
Beam
10.4 m
Draft
5 m
Call sign
WDG9745
IMO
7367134
Official No.
553289
AIS reports
2
On the American registry, Penn No. 4 is a 36.6-metre harbour workboat. Below, she has a 10.4-metre beam and a draft of 5 m. She broadcasts as MMSI 366920960, call sign WDG9745, IMO 7367134. The Master's Mate Safety Initiative Network welcomes Penn No. 4 — free to join, cruiser-run, and always on watch.
Free forever · No credit card · for working boats
Built for boats that work — like Penn No. 4.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
Rig her out — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever Penn No. 4 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 · for working boats
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Penn No. 4 on the map. It hands you the full bridge:
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
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.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
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.
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 Penn No. 4 and switch it all on
Free to join · nothing to install to start · cancel anytime
About Penn No. 4
What kind of vessel is Penn No. 4?
Penn No. 4 is a Towing Vessel flagged to United States of America.
What is Penn No. 4's MMSI?
Penn No. 4's MMSI is 366920960. Call sign WDG9745. IMO 7367134.
How big is Penn No. 4?
Penn No. 4 is about 36.6 m long, 10.4 m on the beam, drawing 5 m.
Is Penn No. 4 on the Master's Mate Safety Initiative Network?
Not yet. If Penn No. 4 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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