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.
Offshore Supply Vessel
Mr. Sidney
MMSI 368020000 · Call sign EX343
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
84.7 m
Beam
18.3 m
Draft
7.3 m
Call sign
EX343
IMO
9529671
Official No.
674209
AIS reports
7
Mr. Sidney, a harbour workboat registered in the United States, measures 84.7 metres on deck. Below, she has a beam of 18.3 m and a draft of 7.3 m. On the registers she's MMSI 368020000, call sign EX343, IMO 9529671. Claim Mr. Sidney free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.
Free forever · No credit card · for working boats
Built for boats that work — like Mr. Sidney.
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 Mr. Sidney 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 Mr. Sidney 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 Mr. Sidney and switch it all on
Free to join · nothing to install to start · cancel anytime
About Mr. Sidney
What kind of vessel is Mr. Sidney?
Mr. Sidney is a Offshore Supply Vessel flagged to United States of America.
What is Mr. Sidney's MMSI?
Mr. Sidney's MMSI is 368020000. Call sign EX343. IMO 9529671.
How big is Mr. Sidney?
Mr. Sidney is about 84.7 m long, 18.3 m on the beam, drawing 7.3 m.
Is Mr. Sidney on the Master's Mate Safety Initiative Network?
Not yet. If Mr. Sidney is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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