The Citizen Chrono Master stands as an icon of precision and craftsmanship in Citizen’s storied history of watchmaking. First introduced in 1967, this high-end watch was designed to meet chronometer-grade standards of accuracy, akin to the prestigious chronometer certifications of mechanical watches. However, due to restrictions on using the "chronometer" designation outside Switzerland, Citizen ingeniously rebranded the series as "Chrono Master," setting it apart with the signature eagle mark proudly displayed on the dial and case back.

Building on the legacy of Citizen’s earlier 1962 hand-wound "Chronometer" watches, the ChronoMaster offered both hand-wind and automatic movements, catering to a range of preferences that certainly make it fascinating.

Today we're offering this beautiful and unused Ref.4-520840Y as the Day-Date automatic variant of this series.

The silvery-white sunburst dial is a visual treat, with a minimalist yet striking layout. The oval day window at 12 o’clock displays days in Japanese (Sundays in red and weekdays in black), while the date window at 3 o’clock provides additional functionality. Applied hour markers, polished hands with a central Onlyx black line, and subtle inscriptions create a harmonious aesthetic. Notably, the silver Citizen logo beneath the day window and the iconic eagle emblem above 6 o’clock reflect the watch’s premium status.

The case design is equally impressive, boasting clean lines, sharp angles, and polished surfaces that exude sophistication. With a lug width of 18mm and a slightly domed mineral crystal featuring a concave inner surface, the watch achieves a remarkable depth. This Chronomaster is powered by the automatic Cal.5240 with 33 jewels, beating at 18,000 BPH. It can be hand-winded, has a quick set date, and hacks for better time settings. The day changes by advancing the hour hand past midnight.

A true gem of Japanese vintage craftsmanship, unused examples of Citizen’s Chrono Master are incredibly rare—especially one like this, complete with its original straps and tag. If you've been looking to experience the Chrono Master series, this exceptional reference will make a perfect addition to your collection.
 
The watch currently works flawlessly and it will be sold as is to retain it's original state. Please let us know if you wish to service it.
 
Shipped from Tokyo, Japan