AhaBulbStuff Everyone Should Know
AhaBulb: Stuff Everyone Should Know · ahabulb.com/boat-isolated-danger-mark

A black buoy with red horizontal bands and two black balls on top marks what?

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  1. An isolated danger you can pass on all sides
  2. The middle of a safe channel
  3. A mooring spot for visitors

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References

  1. 33 CFR 62.29, Isolated danger marks www.ecfr.gov/current/title-33/part-62 Checked 2026-10-09.

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