Centuries of watch craft have done little to diminish the thirst for horological innovation. More than 75 years after the first Oris pilot’s watch took off, the Swiss manufactory has invented the Big Crown ProPilot Altimeter, the world’s first automatic mechanical timekeeper with a built-in mechanical altimeter. Unlike Suunto’s digital height trackers, this design is all moving parts: beneath the glass — and sharing case space with a Cal. 733 movement — is an android barometer measuring air pressure and altitude (in your choice of feet or metres, depending on the model).

The highly engineered watch has caught the eagle eyes of the Groupe d’Intervention de la Gendarmerie Nationale (GIGN), the French police force’s elite special ops unit that’s typically required to carry out 6,000 to 7,000 parachute jumps each year. The GIGN offered to put the watch through its paces in the field — or, rather, the sky — and were so taken with its rugged reliability they have put their name and insignia to a limited edition run of 500 ProPilot Altimeters. It’s literally time to fight crime.

CHF 3,900, available from September Oris.ch