The watch matching this description is the Breguet Classique Alarm Reference 3600 (specifically reference 3600BA/12/2VU for the yellow gold variant). Produced primarily from the mid-to-late 1990s into the early 2000s, this timepiece is a highly collectible, "Investcorp-era" complication that blends traditional haute horlogerie with a mechanical alarm function.

• Dual-Crown System: The watch features a crown at 4:00 for manual time-winding and time-setting, alongside a crown/clutch system at 2:00 dedicated entirely to arming, disarming, and setting the alarm.

• Ultra-Precise Alarm Disk: Unlike most vintage alarm watches that only allow you to set an alarm to the nearest 10 or 15 minutes, the Breguet 3600 features an inner rotating center disk with independent hour and minute lozenge (diamond) indicators, allowing the alarm to be set precisely to the exact minute.

• Date Aperture: A clean date window is located at the 6 o'clock position. The date is advanced using a dedicated quick-set pusher integrated into the side of the case band.

• Case Material: 18k Solid Yellow Gold (featuring Breguet's signature cold-rolled, hand-finished coined case flanks and individually welded straight lugs).

• Case Diameter: 39 mm (excluding crowns and adjusters), with a relatively slim 12.1 mm profile that fits cleanly under a dress cuff.

• Dial: Solid gold base coated in silver with hand-cut guilloché patterns. It features radial Roman numeral hour markers on a smooth outer track and blued steel open-tipped Breguet hands.

• Movement: Caliber 579 automatic self-winding movement (derived from the historic Lemania 2980/Omega 980 caliber), operating at 21,600 vph with 19 jewels and a 40–45 hour power reserve.

• Case Back: Solid 18k yellow gold back, secured by 6 screws.