Omega Constellation 18 CT Yellow Gold Electronic Chronometer wristwatch with sweep seconds hand & date aperture at 3 o'clock. This is an early electronic movement watch (circa 1969) powered by a Bulva tuning fork operated at a frequency of 300Hz. The gold case is hallmarked. The crown is original Omega and the screw-on back has the observatory logo in the center. The original heavy 18 CT gold strap is fully hallmarked. Comes with original certification seal, box and outer box.