Unless this is a
secondary light, to an already legal one, I would suggest looking for an anchor light that complies with the COLREGS definition of a navigation light. We are required by law to display navigation lights that meet the minimum standards.
Lot of snake oil salesmen out there willing to steal your money and give you lights that don't meet the legal requirements.
Known legal navigation lights have passed compliance testing and will be stamped/embossed USCG 1nm, 2nm etc. or ABYC A-16...
This is a
known compliant navigation light.