News · Biver

Biver Builds Its First Steel Watch Around a New Calibre

The 38 mm AB pairs a hand-wound 120-hour movement with an onyx and gold dial, and avoids the obvious steel-case shortcut.

Hen & Mills Editorial · 4 min read · 17 October 2026

• Biver has introduced its first steel watch, the 38 mm AB, with a new hand-wound calibre and a case smaller than its earlier models.
• The dial combines black-treated solid 18-carat yellow gold with polished onyx, while a five-link steel bracelet includes a 4 mm adjustment link.
• Biver directs buyers to register interest, lists no public price on its watch page, and supplies both a steel bracelet and calf-leather strap.

When a young independent watchmaker moves from precious metal to steel, the obvious move is to keep the old watch and change its case. Biver has taken the longer route. Its AB, short for Acier Biver, has a new hand-wound calibre, a smaller case and a dial that is anything but an exercise in economy. According to the maker's 14 October editorial note, the request for a steel Biver came from its collectors. The result is the Biver AB.

A smaller case with a deliberately familiar finish

The AB measures 38 mm across and 9.8 mm thick, making it Biver's smallest case so far. That matters more than the material change alone: a compact case gives the elaborate dial room to command attention without asking the wrist to carry a large piece of polished metal. Biver brushes the flanks and polishes the edges. Turn it to the side and the two finishes should help separate the case's curves from the bracelet, although no photograph can tell us how it will feel after a full day on the wrist.

Steel is an unusual backdrop for the AB's dial. Under the dark treatment is solid 18-carat 2N yellow gold, while a polished onyx ring carries a gold minute track. There is a little theatre in that construction, but it is contained within a black and gold palette. The small seconds at six o'clock and a thin power-reserve arc at twelve make the dial functional without placing another large display over the stone. I initially wondered whether the metal and onyx would be too much for a 38 mm watch; the restraint of the layout makes a better case for it.

The maker's product page gives the case an 8 ATM water-resistance rating and 19 mm between the lugs. Neither figure turns the AB into a sports watch, and Biver does not present it as one. The rating is nevertheless a useful piece of information for a watch intended to be worn rather than kept in a box, while the narrow lug span suits the smaller case. Biver has not published a lug-to-lug measurement on the page, so that part of the fit remains a question until the watch can be tried on.

The first hand-wound Biver calibre

Calibre JCB-004 is Biver's first hand-wound movement, made for this model rather than carried across from the Automatique. Its stated reserve is 120 hours. On a watch with a visible power-reserve display, the point of that duration is not a boast about leaving it in a drawer; it gives the wearer a useful margin while the arc makes the state of wind easy to judge. Pulling the crown resets the small seconds to zero, a practical touch when setting the hands precisely.

Turn the watch over and the movement's materials depart from the usual steel-and-brass story. Biver specifies a PD210 white-gold alloy for the mainplate and bridges and 2N yellow gold for the gear train. The maker also says one watchmaker builds each piece from start to finish, assembles it twice, strips and cleans it between builds, then puts it through three weeks of testing. Those are workshop claims from Biver, rather than a substitute for an independent timing result, but they explain where the brand has chosen to spend its effort.

The five-link steel bracelet is a significant part of the design, not a generic way to attach a new case to the wrist. Biver says it contains more than 300 components, with mixed brushed and polished upper surfaces and a fully polished underside. A patented adjustment link offers 4 mm of movement. That is a more useful detail than another decorative flourish because bracelets with small, rigid links can feel perfect in the morning and tight later in the day. An anthracite Bahia calf-leather strap comes with the watch if the bracelet's visual weight is not wanted.

Biver AB pricing and availability

Biver directs buyers to register their interest through its website and says the AB is available through its retail partners and directly from the brand. Its public product page does not display a list price. The watch carries a four-year warranty. No Australian price or local delivery date appears on that page, so buyers here will need a quote from Biver or an authorised retailer.

The most interesting part of the AB is its refusal to treat steel as a cheaper costume for an existing watch. The new movement, gold and onyx dial, and purpose-built bracelet are expensive decisions in a 38 mm package. Whether that package is worth the inevitable high price is a personal call, particularly without a number from the brand. What it does establish is that Biver's first steel watch has an identity of its own.