When the Seamaster Chronostop launched, the watch was afforded many of the same technical innovations and refinements as Omega’s top-of-the-line sports watches, carrying Omega’s manual-winding, calibre 865 at its heart. Based upon a Lemania ebauche, and beating at 21,600 A/h, this 17-jewel movement was derived from the famed calibre 861 (used in the Omega Speedmaster), yet the calibre 865 was only ever used in the Chronostop. With its extreme accuracy, shock-resistance and internal anti-magnetic protection (owing to its Incabloc shock absorber and and mono-metallic balance respectively), the calibre 865 was an excellent addition.
The Seamaster Chronostop is a unique type of chronograph - similar to that of a fly-back, using a single pusher to operate the stopwatch function. Pressing the pusher once starts the chronograph seconds-hand. Pressing again, and keeping the pusher depressed, stops the hand and holds it in place. Releasing the pusher then resets the chronograph seconds hand back to zero.
One of Omega’s largest vintage models, the Seamaster Chronostop has a tonneau shape case measuring 41mm (excluding the crown and pusher). This elegant, tonneau form and deeply- polished bevelling allow the watch to wear comfortably and discretely on the wrist. The top of the case displays a brushed, “sun-burst” surface, seen in many examples from late 60’s and 70’s and seldom seen today. The reverse of the watch is polished, with a screw-down case back bearing the engraved Hippocampus, found on many Omega watches. The Omega hallmark, 'WATERPROOF' and ‘TESTED 120M' are also visible.
Beneath the raised Omega box-crystal (with an Omega hallmark etched in the centre), the matte-black dial of this Ref. ST145.007 demonstrates sporting intentions, with a fixed inner-tachymeter allowing the user to measure the speed of a travelling object, over a fixed distance. Within the tachymeter is a contrasting, off-white, chapter-ring, with black markers for minutes and chronograph seconds. The dial is faceted, with applied polished-steel indexes, while “OMEGA CHRONOSTOP” and “SEAMASTER” are printed in white at 12 and 6 o’clock respectively. The luminous baton hands are white, offering maximum legibility, with an orange chronograph seconds hand, matching the colour of the Omega logo on the dial.
This full-set, Omega Chronostop ST145.007 comes fitted with a grey suede strap and steel tang buckle.
Viewings can be arranged in Central London.