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Round titanium chronograph with blue dial and bracelet, sapphire crystal, 43.00mm case

Citizen

Citizen Tsuku-yomi Chronograph Blue Dial Eco-Drive 100M BY1010-81L 43.00mm Titanium Watch

SKU CH-91CZ-MEG0C

A solar-powered titanium chronograph with moon-phase display, sapphire crystal and 100 m water resistance

  • Watch movementSolar
  • Product shapeRound
  • Watch face colorBlue
  • Dial markingsIndex
  • Display typeAnalog
  • Date displayDate
  • Eco-Drive solar movement powers the watch without battery changes
  • Super Titanium case and bracelet deliver lightweight strength and corrosion resistance
  • Sapphire crystal protects the blue dial from scratches
  • 100 m water resistance suits swimming and snorkelling
  • H874 calibre adds chronograph and moon-phase functions

Super Titanium Eco-Drive Chronograph

The Citizen Tsuku-yomi BY1010-81L is a solar-powered chronograph built from lightweight Super Titanium for the case and bracelet. A blue dial with index markers and a day-date display sits under sapphire crystal. Water resistance to 100m suits swimming and snorkelling. The deployment clasp secures the bracelet on the wrist.

Solar Movement Daily Reliability

The Eco-Drive calibre H874 converts any light source into electrical energy, removing the need for periodic battery changes. A full charge provides a long power reserve so the watch keeps running through extended periods in low light. The screw-down crown maintains the 100m seal during everyday wear and water exposure.

43mm Case Defines Wrist Presence

The 43.00mm titanium case diameter determines how the watch sits on the wrist and whether it fits under a shirt cuff. Buyers needing a smaller or larger profile should check this dimension against their preference before purchasing.

How it compares

Measured against everything we stock in Analog & Digital Wristwatches, at today’s prices. Recalculated every night.

Price $500.99
Pricier than about 90% of the 2,679 comparable items (median $130.99).

Specifications

Product
Brand nameCitizen
Design styleChronograph
Watch face colorBlue
Item conditionNew
Display
Display typeAnalog
Size & build
Main materialTitanium
Product shapeRound
Strap materialTitanium
Closure typeDeployment Clasp
Bezel typeFixed Bezel
Case constructionScrew Down Crown
Housing materialTitanium
Case size43 mm
Watch glassSapphire Crystal
Environment & compliance
Water resistance100m
More details
Watch movementSolar
Dial markingsIndex
Date displayDate
Suitable forMale

Questions about this item

Does the Eco-Drive movement generate noticeable heat when worn continuously?

The solar-powered Eco-Drive movement has no battery to replace and produces no perceptible heat during all-day wear.

What strap tools are required to adjust the Super Titanium bracelet?

The titanium bracelet uses a deployment clasp with micro-adjustment holes; a spring-bar tool or pin pusher is needed to add or remove links.

Will the 43.00 mm case and sapphire crystal sit flush under a standard shirt cuff?

The 43.00 mm Super Titanium case and domed sapphire crystal have a low profile that slides easily under most business-shirt cuffs.

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