Extraordinary prototype Omega wrist chronograph, Calibre 33.3 CHRO T1-T2

A very rare model fitted with a calibre 33.3 CHRO T1 (possibly T2) from 1937 to 1941, as shown in the catalogues provided by Omega.

Off-white enamel dial with tachymeter-telemeter display, outer telemeter scale (0–20 km) and inner tachymeter scale (300–20 km/h) in blue, gold baton hour markers, gold hands. Fully polished Staybrite steel case, bevelled bezel, start/stop push-button at 2 o’clock, reset push-button on the crown. Small continuous seconds sub-dial at 3 o’clock and 30-minute counter at 9 o’clock (both recessed). The case features a single push-piece at 2 o’clock and a crown with a push-piece at 3 o’clock, matching the design of the 1937 Model 3531 wristwatch, ‘Omega Wrist Chronograph Prototype’. Prototype of the 33.3 CHRO T1. The case and dial are similar to the model 1142 wristwatch. Ibid., 1943, with the same tachymeter-telemeter dial, but with two pushers at 3 and 4 o’clock and no pusher on the crown. Calibre 33.3 CHRO T3.

Possibly period acrylic (Plexiglas) crystal, and non-original strap

Identification: Case reference 901.596 and movement serial number 9.380.973.

In working order with signs of wear, as shown in the photographs.

Case diameter: 38 mm