Oris has a proud tradition of movement development. Over the course of the Hölstein-based brand’s 100-plus years of operation, the company had developed some 229 in-house calibres. But Oris made its last calibre in 1982. From this point, the brand switched to ETA (and later Sellita Works) ébauches.

In 2014, Oris fired up the home forges again, celebrating their 110th anniversary with the appropriately named calibre 110. An impressive tractor of a movement, the 110 was a hand-winder with 10 days of power reserve coming off a single mighty barrel. A statement, and a big one at that, but — due to its scale — one with limited application in Oris’ assortment.

The same cannot be said about the brand-new calibre 400, which has been designed by Oris from the ground up, with components supplied from Oris’ network of suppliers. This movement is an enhanced alternative to the 733 — based upon the SW 200-1 — that powers a significant percentage of Oris watches. Oris, rather than opt for incremental improvement such as boosting the power reserve from 38 to 50 or 70 hours, has pulled out all the stops. Calibre 400 offers a phenomenal five days (or 120 hours) of autonomy, thanks to twin barrels with extended mainsprings. The fun doesn’t stop there, though — Oris has also deployed a range some 30 non-ferrous and anti-magnetic components in the movement, including a silicon escape wheel and anchor. These improvements will lessen the impact of magnetic fields that permeate our everyday life, resulting in greater accuracy over time (Oris rate this watch as running between −3/+5 seconds). Another area that Oris’ techs have marked down as a problem area in the past is around the ball-bearing system of the oscillating weight. To this end, the calibre 400 uses a low friction slide-bearing system. These improvements mean that Oris is comfortable offering not only a 10-year warranty on watches with the calibre 400, but also a 10-year service interval. It’s a momentous move for the value-oriented brand, one which enhances its offering and sets them up well for future developments.

So that’s the movement, but what watch has Oris chosen to debut this beast in? None other than their perennially popular modern diver, the Aquis. From the dial side, you could be forgiven for thinking that this was a “regular” Aquis, with strong lines and a gorgeous gradient blue dial. Look closer at that 43.5mm case, and you’ll spot a few tell-tale signs that something special is going on. The date display is black and slightly larger than normal. There’s also a discreet line of text saying “5 days”, that really gives the game away. Flip the watch over, though, and you get the whole show — thanks to a sapphire display back larger than any an Aquis had ever seen before. Finished in Oris’ usual industrial aesthetic, the architecture is still pleasing, with the balance and the barrels visible through the openworked rotor. Once you’ve finished taking the calibre 400 in, you might also notice that the bracelet boasts a brand-new quick-change system, further adding to the functionality. The Oris Aquis Date Calibre 400 has a suggested price of USD 3,500 on a bracelet, compared with USD 2,200 for a comparable model without the new movement. Given the significance of the specs bump, it’s safe to say that Oris’ reputation for value is intact.