[Code of Federal Regulations] [Title 33, Volume 2] [Revised as of July 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 33CFR174.23] [Page 810] TITLE 33--NAVIGATION AND NAVIGABLE WATERS CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PART 174--STATE NUMBERING AND CASUALTY REPORTING SYSTEMS--Table of Contents Subpart B--Numbering System Requirements Sec. 174.23 Form of number. (a) Each number must consist of two capital letters denoting the State of the issuing authority, as specified in Appendix A of Part 173 of this chapter, followed by-- (1) Not more than four numerals followed by not more than two capital letters (example: NH 1234 BD); or (2) Not more than three numerals followed by not more than three capital letters (example: WN 567 EFG). (b) A number suffix must not include the letters ``I'', ``O'', or ``Q,'' which may be mistaken for numerals.