Tudor - M7939A1A0NU-0001 Black Bay 58 Stainless Steel / Black / Bracelet

Tudor M7939A1A0NU-0001 description

The Tudor Black Bay 58 M7939A1A0NU-0001 debuted in 2026 as an updated 39mm stainless steel diver fitted here with a five-link bracelet. As part of the current Black Bay 58 generation, it combines the line’s established mid-century-inspired proportions with a revised 11.7mm case, Master Chronometer certification, and a series of smaller design updates to the dial, bezel, crown, and hands.

Its stainless steel case measures 39mm in diameter, 11.7mm in thickness, and 47.8mm lug to lug, retaining the compact proportions that define the Black Bay 58 within Tudor’s dive watch range. The case is finished with polished and satin-brushed surfaces and fitted with a unidirectional rotatable bezel in stainless steel with an anodised aluminium insert. The insert features a red triangle and curved numerals that follow the outline of the outer ring, while the redesigned screw-down crown sits flush to the middle case band and is signed with the Tudor rose in relief. Water resistance is rated to 200 metres, and the crystal is domed sapphire.

The dial is matt black and domed, with applied hour markers and the familiar Black Bay handset. In this updated execution, the dial text has been reduced to two lines, bringing it in line with Tudor’s Master Chronometer-certified models, while the hands show a slightly pinched base. The seconds hand retains the lollipop form associated with Tudor’s early divers’ watches, and the absence of a date keeps the layout notably balanced and direct.

Inside is the Tudor Manufacture Calibre MT5400-U, a self-winding mechanical movement with 27 jewels, bidirectional winding, and a METAS-certified 65-hour power reserve. It is both COSC-certified and certified as a Master Chronometer by METAS, with resistance to magnetic fields up to 15,000 gauss and a daily precision tolerance of 0/+5 seconds under METAS testing criteria. The movement uses a variable inertia balance with micro-adjustment screws, a non-magnetic silicon balance spring, and a stop-seconds function for precise setting.

This reference is fitted with a five-link stainless steel bracelet with polished and satin finishes and a Tudor T-fit clasp. Among the new Black Bay 58 bracelet options, this configuration gives the watch a more continuous and slightly dressier profile than the rivet-style three-link version, while retaining the same tool-free rapid adjustment system with five positions across an 8mm range.