U.S. Official No. 1037123
Not yet on Master's MateOut of the United States, SB 4 is a 9.5-metre cargo vessel. SB 4 has a 2.6-metre beam and a 1.5 m draft. Look for U.S. official number 1037123. It's free to add SB 4 to the Master's Mate Safety Initiative Network — like AAA for the ocean, run by the cruisers who use it.
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
Joining the Safety Initiative Network doesn't just put SB 4 on the map. It hands you the full bridge:
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