The 79000N is the Black Bay 54, introduced in 2023. The name refers to 1954, the year of Tudor's first dive watch, reference 7922, and the Black Bay 54 follows that model more closely than earlier Black Bays: a 37 mm case and a sober look in keeping with the dive watches of the 1950s.
At 37 mm the Black Bay 54 is the smallest dive watch in the Black Bay family, smaller than the 39 mm Black Bay Fifty-Eight. The in-house calibre MT5400 has no date, a power reserve of about 70 hours and a COSC certificate. The bezel turns in one direction, and the watch is water-resistant to 200 metres. It comes on a steel bracelet or on a strap.
A smaller case sits close to the wrist and slips easily under a cuff, which makes the Black Bay 54 suitable as an everyday dive watch. On a pre-owned example we look at the bezel and insert, the luminous material, the bracelet and clasp, and the set. Because the reference is recent, an example often still carries manufacturer's warranty; the date on the guarantee card is decisive.