Seiko Prospex Divers GMT 'Marine Green' 42mm Mens Watch - 1968 Modern Re-interpretation

Ref. SPB381J1

The SPB381J1 belongs to a trio of watches Seiko built around a single milestone: the introduction of the 6R54, their first mechanical GMT calibre in a diver's watch. The anchor point for the design is the 1968 one-piece diver, Japan's first hi-beat diver and the watch that set the direction for everything Seiko built in the category afterwards. Returning to that case shape to house a genuinely new movement rather than a cosmetic refresh gives this watch a clearer reason to exist than most anniversary pieces manage. The 6R54 earns attention beyond its GMT function. The home-time hand adjusts independently in one-hour steps without disturbing the running hands — a small thing that matters on a travel watch — and a 24-hour scale on the rehaut keeps the second timezone readable without cluttering the marine green dial. At 12.9mm thick for a 200m-rated diver with GMT complication, the case sits lower than the rating might suggest, and the 42mm footprint with its contoured edges keeps 176g of steel from feeling punishing over a full day. The ceramic bezel matches the dial colour and, by reviewer consensus, turns with the kind of resistance that feels deliberate without being effortful.

Reference

SPB381J1

Brand

Seiko

Case size

42mm

Case thickness

12.9mm

Lug width

20mm

Case material

Stainless steel

Case shape

Round

Dial

Green

Crystal

Sapphire

Movement

Automatic

Calibre

6R54

Functions

GMT, Date

Water resistance

200m

Bracelet / strap

Stainless steel bracelet

Strap colour

Silver

Clasp

Three-fold clasp

Lume

LumiBrite

Retailer

Goldsmiths