Citizen Tsuki-yomi A-T BY1010-57H – Super Titanium Eco-Drive Atomic Moonphase Watch

The Citizen Tsuki-yomi A-T BY1010-57H is a sophisticated Eco-Drive atomic timekeeping watch that combines advanced Citizen technology with a refined sport-luxury design. Featuring a gray dial, silver-tone Super Titanium™ case and bracelet, and a distinctive moonphase display, this model offers everyday comfort, durability, and high functionality in a modern 43mm profile.

Powered by Citizen’s light-powered Eco-Drive technology, the BY1010-57H runs on any light source and eliminates the need for regular battery replacement. With Atomic Timekeeping, Radio Control, World Time in 24 time zones, a Perpetual Calendar, and Day-Date functionality, this watch is built for those who appreciate precision, convenience, and innovative Japanese watchmaking.

Design Overview

The 43mm silver-tone Super Titanium™ case gives the Tsuki-yomi A-T a strong yet lightweight presence on the wrist. The gray dial is inspired by the surface of the moon, with a moonphase window positioned at 6 o’clock for a refined and technical look. Its matching Super Titanium™ bracelet provides durability and comfort, while the sapphire crystal offers superior scratch resistance and hardness for long-term wear.

With WR100 / 10 Bar / 333 ft water resistance, this model is suitable for swimming, showering, and snorkeling, making it a practical choice for daily wear as well as travel.

Key Features

• Citizen Tsuki-yomi A-T Collection – Moonphase design with advanced timekeeping technology
• Eco-Drive Movement Caliber H874 – Powered by any light source
• Atomic Timekeeping / Radio Control – Designed for highly accurate timekeeping
• Moonphase Display – Displays the current phase of the moon
• World Time in 24 Time Zones – Ideal for travel and international use
• Perpetual Calendar – Automatically adjusts for date changes
• Day-Date Display – Practical everyday functionality
• Super Titanium™ Case and Bracelet – Lightweight, durable, and comfortable
• Sapphire Crystal – Superior scratch resistance and hardness
• WR100 / 10 Bar / 333 ft Water Resistance – Suitable for swimming, showering, and snorkeling

Case & Exterior

• Model: BY1010-57H
• Collection: Citizen Tsuki-yomi A-T
• Case Material: Silver-Tone Super Titanium™
• Case Diameter: 43 mm
• Lug Width: 22 mm
• Dial Color: Gray
• Crystal: Sapphire Crystal
• Band: Super Titanium™ Bracelet
• Clasp: Fold Over Clasp with Push Buttons
• Weight: 105 g

Movement & Performance

• Movement: Citizen Caliber H874
• Technology: Eco-Drive, powered by any light source
• Timekeeping: Atomic Timekeeping / Radio Control
• Functions: Moonphase, World Time in 24 Time Zones, Perpetual Calendar, Day-Date
• Water Resistance: WR100 / 10 Bar / 333 ft

Why Choose the Citizen Tsuki-yomi A-T BY1010-57H?

The Citizen Tsuki-yomi A-T BY1010-57H is an excellent choice for anyone looking for a Citizen moonphase watch, a Super Titanium Eco-Drive watch, or a radio controlled atomic watch with world time. It brings together elegant design, lightweight titanium comfort, advanced Japanese watch technology, and practical everyday durability.

If you are searching for a Citizen gray dial watch, a 43mm titanium men’s watch, a light-powered atomic timekeeping watch, or a premium Citizen Tsuki-yomi A-T Eco-Drive timepiece, the BY1010-57H stands out as a refined and highly functional option.

Instruction Manual for Caliber No. H874

For more details, visit the official Citizen website here.

Warranty:
This model includes Citizen’s 5-Year Limited Warranty for added confidence in your purchase.

▶︎Processing Time & Shipping Policy
▶︎Refund policy
We only carry CITIZEN USA products.
▶︎We DO ship internationally.