The Oris Aquis Date Calibre 400 41.5mm Bi-Colour in Green and Aqua Blue

Oris introduced the in-house calibre 400 automatic in late 2020 that replaced Sellita counterparts in higher-end models and joined the in-house, hand-wound calibre 110 from 2014 (and subsequent variants). Major improvements like an anti-magnetic escapement and five-day power reserve overshadowed the always reliable Sellitas, but prices remained (relatively) accessible for the updated Aquis Date models. The latest Oris Aquis Date Calibre 400 duo come with 41.5mm cases and 18k gold bezel edges, and the latter adds some panache to the already stylish series. You also have the choice of two dial colours and either an integrated bracelet or rubber strap, so there’s a nice variety on tap as well. 

The new collection matches the aesthetic of last year’s introduction of the 41.5mm Aquis Date Calibre 400, but gold accents really dress things up. As mentioned, the unidirectional rotating bezel has an 18k gold finish on the outer edge, while the detailed 60-minute diver’s scale has a matching gold colour. The two models come with forest green and aqua blue dials (already in the collection), so the ceramic bezel inserts are either a complementing green or blue. A domed sapphire crystal with an interior anti-reflective coating protects the dial, while the case back has a mineral glass exhibition window. The screw-down crown is protected by the familiar screwed guards and water-resistance is rated at 300 metres. You have the choice of the brushed/polished integrated three-link bracelet with folding clasp and diver’s extension, or a supplied matching green or blue rubber strap with folding clasp and extension. All come with quick-release levers for easy exchanges without tools. 

Although the green or blue sunray dials have been seen before, they now come with gold (coloured) applied indices with Super-LumiNova inserts. The central hands are also gold with Super-LumiNova. The black date window at 6 o’clock still has white print, but the dial text is now in gold. These are otherwise the same as last year’s Oris Aquis Date Calibre 400 41.5mm models with green or blue dials, but the gold accents really do make a difference. 

Powering the new pair, as the name implies, is the in-house calibre 400 automatic. It’s quite a movement and again a real upgrade from the Sellita SW200-1 autos. Significant improvements include a chronometer level of accuracy at -3/+5 seconds per day (exceeding the minimal standard), a power reserve of 120 hours via twin barrels (compared to just 38 hours) and the movement is highly anti-magnetic with a silicon escapement. It beats at 28,800vph (4Hz) and has 21 jewels, and functions include central hours, minutes, hacking seconds and date. 

The new Oris Aquis Date Calibre 400 41.5mm Bi-Colour Gold models retail for CHF 4,000, which is about CHF 800 more than the standard Calibre 400 models. That’s still a reasonable price for pro-level Swiss divers with 18k gold accents and an impressive in-house calibre. They also come with a 10-year warranty and 10-year service intervals. For more information and orders, please visit www.oris.ch.