SEA MARK BOATS HIN Decoder — MIC ADL
Hull Identification Numbers beginning with ADL were assigned by the US Coast Guard to SEA MARK BOATS of ROCKY POINT, NC. The builder is listed in the USCG MIC database. Enter the full 12-character HIN below for build date, model year, and serial — free, no account.
MIC
ADL
Location
ROCKY POINT, NC
In business
since 1972
Status
Listed active in USCG records
SEA MARK BOATS built hulls across both HIN eras (1972–present): boats before August 1984 carry legacy straight-year or model-year date codes; later hulls use the current month-letter format. The decoder handles all three.
How a SEA MARK BOATS HIN breaks down
A current-format (1984–present) Hull Identification Number is 12 characters. Using the example ADL45678D424 (illustrative):
| Characters | Segment | In example | What it identifies |
|---|---|---|---|
| 1–3 | Manufacturer (MIC) | ADL | Identifies SEA MARK BOATS, assigned by the US Coast Guard. |
| 4–8 | Hull serial number | 45678 | SEA MARK BOATS's own production number for the specific hull (the letters I, O, Q are never used). |
| 9 | Certification month | D | Month built — A=January … L=December (D = April). |
| 10 | Certification year | 4 | Last digit of the certification year. |
| 11–12 | Model year | 24 | The boat’s model year. |
Free · no account · the HIN is on the transom, upper starboard (right) corner
Buying this SEA MARK BOATS? Check it before you pay.
Decoding the HIN confirms the year and serial, but not the safety record. The $9.99 Boat Report adds the full CPSC marine-recall check, a HIN consistency check, a verify-before-you-buy checklist, and the USCG builder record for this hull — one downloadable report, one-time, no subscription. See what's included
SEA MARK BOATS HIN FAQ
What does a SEA MARK BOATS HIN look like?
It starts with the three characters "ADL" — the Manufacturer Identification Code the US Coast Guard assigned to SEA MARK BOATS — followed by a 5-character hull serial and a 4-character date code, 12 characters total. SEA MARK BOATS built hulls across both HIN eras (1972–present): boats before August 1984 carry legacy straight-year or model-year date codes; later hulls use the current month-letter format. The decoder handles all three.
Is SEA MARK BOATS still in business?
USCG records list SEA MARK BOATS of ROCKY POINT, NC in the MIC database (registered 1972).
How do I decode the year on a SEA MARK BOATS HIN?
On current-format HINs the last two characters are the model year and the 9th–10th encode the certification month and year. SEA MARK BOATS built hulls across both HIN eras (1972–present): boats before August 1984 carry legacy straight-year or model-year date codes; later hulls use the current month-letter format. The decoder handles all three. Enter the full 12-character HIN above and the decoder works it out, including the legacy formats.
Where is the HIN on a SEA MARK BOATS boat?
On the outside upper-starboard (right) corner of the transom, within two inches of the top — required by 33 CFR 181.29. Since August 1984 an identical duplicate HIN is also molded into an unexposed interior location as an anti-theft measure. Both should match the title, registration, and insurance card exactly.
Is the "ADL" MIC the same as a SEA MARK BOATS serial number?
No. "ADL" is the Manufacturer Identification Code — characters 1–3 of the HIN — that identifies SEA MARK BOATS. The hull serial number is characters 4–8: SEA MARK BOATS's own production number for that specific boat (the letters I, O, and Q are never used). The full 12-character HIN combines the MIC, the serial, and the date code.
Can a SEA MARK BOATS HIN tell me the exact model?
Not on its own. A HIN encodes the builder, hull serial, certification month/year, and model year — not the model name or length. Match the decoded year and serial against SEA MARK BOATS records, the title, or a marine survey to confirm the exact model and configuration.
Other builders in NC
Sources: verified against the USCG Manufacturer Identification Code database (refreshed monthly) · HIN format per 33 CFR Part 181, Subpart C. Reviewed by Sam Reynolds, Lead Researcher, CarWhere. Cite this page: CarWhere, "SEA MARK BOATS HIN Decoder," carwhere.com/hin-decoder/adl, last verified 2026-06-15.