All boats coming into the US and I guess most other areas, have a 12 digit HIN No.
Here is mine DSI00926F404 and here is how to read it.
The first 3 digits are the manufacturers code. Mine is DSI for Dong Seo (manufacturer)
The next 5 digits are the Serial Number. Mine is 00926
The next digit is the month represented by the letter "F". "F" is the 6th letter of the alphabet and so the 6th month is June
The next digit is the date of Certification. Mine is 4. Since there only 12 digits total in the HIN No. I have no idea how they certify anything from the 10th and on up.
The last 2 digits are the year of manufacture. Mine is 04 which means 2004.
In my case, the last 4 digits are F404. This means that my boats Date of Certification was June 4, 2004