Marine Bulbs are light bulbs that are designed for use in marine applications such as boats, yachts, boat slips, marinas, etc. Specific applications for marine bulbs are chart lights, underwater spreader lights, hull lights, navigation lights, courtesy lights, engine lights, etc.
For the Machine lighting system, The Short voltage spikes of 24V boat will over 30V. For example DC 24V boat light system, The operation voltage range of led bulbs must be from 24 volts to 40 volts. DC 36V boat light system, The operation voltage range of led bulbs must be from 36 volts to 60 volts. Please see here link to see how do I choose led lights for boats?