Citizen
Citizen Radio-Controlled Moonphase BY1030-50L Blue
Citizen Radio-Controlled Moonphase BY1030-50L Blue (reference BY1030-50L) — specifications, measurements, watch images and standardized wrist-fit previews for informed comparison.
A 42 mm complication / dress watch with eco-drive radio-controlled quartz movement (H874) and 100 m water resistance.
Best forWearers who prefer refined proportions and a dress-oriented design.
Not ideal forBuyers who need a different size, complication set or strap format.
At a glance
ReferenceBY1030-50L
Model lineRadio-Controlled Moonphase
Production statusCurrent
Watch technology InfoLight Powered (Eco Drive)
DisplayAnalog
Movement InfoEco-Drive radio-controlled quartz
Calibre / operating system InfoH874
Key features InfoDate, Day, Month, 24-hour display, World time, Moon phase, Perpetual calendar, Power-reserve indicator, Light-powered / solar charging, Radio time sync
Complication InfoMoon phase; perpetual calendar; world time
Case diameter Info42 mm
Thickness Info10.7 mm
Lug-to-lug Info42 mm
Power reserve / runtime4320 hours
Water resistance100 m
OriginJapan
Price categoryPremium
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Specifications last verified: 2026-08-07.
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