N.Y. Nav. Law § 57
Every public vessel subject to the provisions of this chapter shall be registered and display the identification number assigned as set forth in section twenty-two hundred fifty-one of the vehicle and traffic law. In addition to the number assigned, each public vessel shall display the letters "PV" not more than six inches above or below the identification number. The letters "PV" shall be not less than five inches in height and maintained in a legible condition so that the letters, "PV", are readily discernible during daylight hours at a distance of two hundred feet. It shall be the duty of every owner to register and display numbers as herein indicated. Violation of this section shall be a violation punishable by a fine of not less than twenty-five nor more than one hundred dollars.
N.Y. Nav. Law § 57