The Black Bay 58 GMT. The travel Tudor at 39mm.

Tudor’s first Black Bay GMT was the 41mm M79830RB, a 14.6mm-thick watch with a Pepsi bezel that many people loved and some found too tall. The 58 GMT is the answer: the same idea in the 39mm Fifty-Eight case at 12.8mm, with a black and burgundy bezel instead of blue and red, gilt markers, and a newer calibre, the MT5450-U, that carries the METAS Master Chronometer certificate on top of COSC. The GMT hand is a true traveller’s hand: the local hour jumps in one-hour steps while the 24-hour hand holds home time against the bezel.

At 65 hours of reserve it runs through a long weekend off the wrist. The rivet-style bracelet has the fake rivets on the sides of the outer links that Tudor uses to nod at its 1950s bracelets, and the T-fit clasp gives about 8mm of tool-free adjustment.

The listing carries the reference M7939G1A0NRU-0001 in the model row and calls it a 39mm automatic with 200 metres, a sapphire crystal and a steel bracelet. The photograph shows the black and burgundy bezel, gilt markers, snowflake hands, the gilt GMT hand, the date at three and the rivet-style bracelet. The thickness, lug width, calibre, both certifications, the reserve and the clasp are Tudor’s published figures for the reference.

The seller is Watchsavings, a marketplace seller. Ask the seller whether it is new with Tudor’s five-year guarantee card, and for the box; the rows we read do not say. Nothing here was measured on the watch.

This is a regular Amazon listing from a marketplace seller with Amazon’s 30-day return window; it is not a Luxury Stores pre-owned unit and the seller has not published a condition. The second button opens the live search for Black Bay GMTs in case this one has sold.

Black Bay 58 GMTs have resold for under new and close to what pre-owned buyers paid, sometimes more, sometimes less; that is a pattern, not a promise, and nothing here is investment advice.