Orion 35 / Open Case Back

Reference 309 is the sapphire-back version of the 35mm NOMOS Orion, with a stainless steel case, white silver-plated dial, gold-coloured indexes, tempered blue hands, and a hand-wound movement. As a long-running Orion reference, it has gone through several movement iterations over time. The current specification lists the DUW 4001 calibre. The case measures 35mm in diameter, 8.7mm in height, and 45mm from lug to lug. It has a domed sapphire crystal front and a domed sapphire crystal case back, distinguishing it from the closed-back version. The Orion case is defined by its rounded, lenticular profile, curved crystal, and tapered lugs. Current specifications list water resistance at 5 atm, an increase from the earlier 3 atm rating. The galvanized white silver-plated dial is free of numerals and uses fine gold-coloured hour markers. The tempered blue steel hands contrast with the pale dial surface, while the small seconds display at 6 o’clock gives the watch its traditional hand-wound layout. The display consists of central hours and minutes with subsidiary seconds. Power currently comes from the NOMOS DUW 4001, a manually wound in-house calibre measuring 10 ½ lignes in diameter and 2.6mm in height. It has 17 jewels and a power reserve of up to 53 hours. The movement is visible through the sapphire crystal back. The watch is supplied on a black Horween Genuine Shell Cordovan strap with an 18mm lug width.