This appears to be a vintage world-time style wristwatch branded FERO Feldmann, marked “23 Jewels” and “10 ATM Tested”. Notable details visible in the photo: • Rotating bezel with world cities such as Sydney, London, Tokyo, Mexico, Chicago • Dark blue dial and bezel with orange lettering • Internal 24-hour/world-time scale • Date window at about 3 o’clock showing “20” • Tachymeter markings on the dial • Cushion-shaped stainless steel case • Likely from the 1970s era, based on the design language and typography The watch looks inspired by the popular compressor/world-time dive watches of that period. FERO was a Swiss watch brand associated with mid-century mechanical watches rather than a major luxury manufacturer.