Federal Requirements for Display of Boat Numbers
Numbers must be painted or permanently attached to each side of the forward half of the vessel. The validation stickers must be affixed within six inches of the registration number.
With the exception of the vessel fee decal, no other letters or numbers may be displayed nearby.
Lettering must be in plain, vertical block characters of not less than 3 inches in height. Spaces or hyphens between letter and number groupings must be equal to the width of a letter other than "I" or a number other than "1".
Provided by uscgboating.org.