Published on January 18th, 2018 | by Daniel Sherman Fernandez


Seiko’s Diving Watch Revisited

Seiko made Japan’s first diver in 1965 with the Reference 62MAS. When introduced in ’65, it used a self-winding automatic movement and was water resistant up to 150 meters. Members of the Japanese Antarctic Research Expedition from 1966 to 1969 were famously supplied with this watch on their mission.

Seiko would continue to develop competency in making diver’s watches and in 1975, under the guidance of engineer Ikuo Tokunaga developed what is arguably considered one of the best dive watches of all time, the Ref. 6159-7010 ‘Tuna’.

The SLA017 is a homage to the 62MASSeiko’s recreation of the original carries the reference number SLA017. To design the SLA017, Seiko turned to Nobuhiro Kosugi, a recipient of the Japan’s prestigious Medal with Yellow Ribbon and Contemporary Master Craftsman awards. Kosugi has honored the design codes of the original as seen in the 3D embossed hour markers, which stand up in sharp relief and yet are an integral part of the dial itself.

Like in the original, the dial uses a luminous dot at twelve o’clock and has the same slim profile case and narrow bezel. While the original had a case width of 37 mm, the reissue uses a 39.9 mm case.

While staying faithful to the original design codes of the watch, Seiko has given the reissue some important updates. It uses a box-shaped sapphire crystal on the case now and the watch is depth-rated to 200 meters. It is also paired with a silicone strap and the case has been treated to make it more durable and scratch resistant.

Underneath sits Caliber 8L35While the original was powered by a slow-beating Caliber 6217 movement, the re-issue uses Caliber 8L35, produced at Seiko’s famed Shizuku-ishi Watch Studio in Morioka. Shizuku-ishi studio is where all of the Grand Seiko mechanical models are hand-made. Caliber 8L35 is essentially a paired down version of the Grand Seiko Caliber 9S55. It is just not decorated or adjusted to Grand Seiko standards.  Caliber 8L35 is used to power Seiko’s SBDX001 Marinemaster MM300.

These new watches draw inspiration from 62MAS but have been updated to meet Seiko’s Prospex standards.

Both watches use a 42.6 mm case that is 13.8 mm thick. The hands are wider and carry Seiko’s superb Lumibrite luminescence for legibility even in dark water. The water resistance has been increased to 200 meters and a sapphire crystal with an anti-reflection coating sits atop the case. The watch is powered by the hacking seconds-equipped Caliber 6R15 used in Seiko’s Presage models.

The case sides feature a Zaratsu polishing line (a tin polishing method that removes all distortion) on the case. Ref SPB051 uses a black dial and a black aluminum bezel and is paired with a steel bracelet while SBP053 uses a blue dial and matching bezel and is paired with an accordion-style silicon strap. These watches will be released in November 2017.

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