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Seiko Astron

Seiko Astron

SolarTitanium

Ref. SSH121J1

Collection: AstronCase size: 43.1mmMovement: 5X53

The Seiko Astron, reference SSH121J1, is a GMT watch with a 43.1 mm titanium case. The case is 12.2 mm thick, with a lug-to-lug measurement of 48 mm and a water-resistance rating of 100 metres. The movement is solar-powered calibre 5X53, which operates for approximately 6 months when fully charged. Over the dial is a sapphire crystal with an anti-reflective coating. The movement has an accuracy of minus 15 to plus 15 seconds per month. The bezel has a ceramic insert. A titanium bracelet fastens with a folding clasp with a three-fold construction.

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Last updated 9 Oct 2026Suggest a correction

TECHNICAL SPECIFICATIONS

GENERAL

Gender

Men

CASE

Diameter

43.1mm

Thickness

12.2mm

Lug to Lug

48mm

Case Material

Titanium

Water Resistance

100m

Crystal

Sapphire Crystal

Bezel Material

Ceramic

MOVEMENT

Movement Type

Solar

Caliber

5X53

Jewels

12 jewels

BRACELET/STRAP

Bracelet/Strap

Titanium

Clasp Type

Fold Clasp

FEATURES & COMPLICATIONS

GMTSolar watch

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FOR WATCH DEALERS

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