The very nature of marine engines, even petrol (gasoline) powered, is for the manufacturers to minimise the amount of electrical components and wiring for both reliability and ease of maintenance and repair.
If you are refurbishing the electrics - perhaps for a new season of boating - then this component, and perhaps some of those listed below maybe required, for use now, or perhaps to keep in the onboard spares locker, just in case?
Add as many components as you wish to the same shopping cart, for example new fasteners to replace those that are corroded or damaged beyond use, and still only pay the same fixed price shipping cost.