At 51 mm diameter, this is certainly a large watch, but after all, Oris call it a tool watch, and it was born to be underwater, strapped over a wet suit. It is a new version of the ProDiver Chronograph introduced in 2009. It has a 100 bar/1,000 metre water resistance, achieved by means of screw-down crown and pushers, screw-in caseback, and a domed watch glass that is 7.1 mm thick and is the heaviest component in the watch.
The bezel is superbly designed, with a black ceramic insert and a black vulcanized rubber ridged edge. The Rotating Safety System is an improvement on the usual unidirectional rotating bezel. In the Oris system, you lift the black surround, which frees the bezel so that you can rotate it to where you need it. Then you lower the rubber surround, which locks the bezel, and you return the surround to its starting position by rotating. It’s a bit more complicated to use than a unidirectional rotating bezel, but it has the advantage that it locks the bezel and so can’t accidentally be knocked out of position in either direction.
The watch has a rubber strap with a sliding sledge clasp, which makes changing length quick and easy. There is also a fine adjustment system on the clasp itself. The watch is supplied with both rubber strap and stainless steel bracelet: the latter also has a diver’s extension.
On the caseband at 9 o’clock is the helium escape valve which protects the watch if it is used in a compression chamber with helium-enriched air. Helium atoms are small enough to infiltrate a watch case, and expansion of the gas during decompression could cause damage. The dial layout is clear, with subdials for chronograph minutes and hours, small seconds at 9 o’clock, and a small date window at 6 o’clock. SuperLuminova is applied to the hour and minute hands, and the hour indices.
The watch is powered by the self-winding Oris calibre 774, which is basically the Sellita SW500, itself a clone of the classic ETA 7750 chronograph movement. 48 hours power reserve. The Oris ProDiver Chronograph is supplied in a case with the extra strap, a tool for strap changing, and an explanatory booklet.
The Oris ProDiver Chronograph, reference 01 774 7727 7154 Set, costs €4,200, 4,500 Swiss francs, $4,650.