Seiko Tuna is the name given to Seiko's range of watches designed for scuba and professional diving. In particular, Seiko made these watches with saturation diving or greater depth diving in mind. All of the watches in the Seiko Tuna range are characterized by protective screwed-on shrouds that have earned them the nickname of “Tuna”.
The Seiko Tuna collection boasts of many firsts. The collection was the first to feature a titanium/stainless steel shroud, a monocoque case, an L-shaped gasket, and a vented rubber strap. Primarily built for functionality, the Seiko Tuna watches can withstand great depths as tools for professional divers.
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| Seiko Prospex Profesional 1000M Emperor Tuna Ref. SBDX038 / SLA042J1 |
Built in 1975, the first Seiko Tuna watch was created in response to a letter the company received in 1968. A saturation diver from Kure City in the Hiroshima, Japan sent a complaint regarding Seiko divers watches, which the company had been making since 1965. These pre-Tuna models were not robust to impact and could not withstand exposure to deep underwater pressure for prolonged periods.
Seiko engineers took on the challenge to create the “ultimate professional diver’s watch. These engineers, led by Ikuo Tokunaga, decided to develop the new Seiko Tuna watches for saturation diving from the start. Tokunaga and his team began development in 1968 and released the first Seiko Tuna watch seven years later with more than 20 patents.
The luxurious yet overbuilt timepiece is powered by an iconic high grade 8L35 calibre which is a genuine undecorated to the Grand Seiko caliber 9255, the first high-end autoamtic movement from Seiko . This movement is only used in a handful of Prospex “marine master” dive watches in the past few years. Made with the utmost care by Seiko's skilled craftsmen in the Shizuku-ishi Watch Studio in Morioka, Japan, this calibre operates at 28.800 bph (10 beats/sec) and has a power reserve of 50 hours. Built with 26 jewels, this movement is with an expected accuracy within -10/+15 seconds per day.
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| Titanium Inner Case with rose gold hard coating and Ceramic Shroud |
While faithful to the original bi-tone aesthetics of 1978 Ref. 7549 Golden Tuna Diver, the greatest advance of the “Tuna” design is the usage of Seiko’s Ever-Brilliant bezel in its shrouded case construction. Providing greater corrosion resistance, this one piece inner titanium case is fitted with the L-shaped gasket for helium resistance; and gets topped with its brilliant rose-gold hue bezel, cladded within a matte ceramic shroud, which sets it apart from other Seiko timepieces. The shrouded monocoque case embodies three solid materials, in with the first use of Ever-Brilliant coating.
And as the Tuna was mend for true professionals, Seiko decorated it with the upmost modern materials ever available for durability. Enhanced by the super-hard coating which allows for greater scratch resistance, this mono-bloc case has a PERN value that is 1.7 times higher than that of the steel used in other high-end watches. Armed with years of experience and innovative techniques, the Seiko team overcame the obstacles of using this stainless-steel material to bring a whole new level of durability to dive watches with the combination of Ever-Brilliant Steel bezel, titanium body, and ceramic outer-shroud of the re-creation.
The case of this timepiece is analogous to the original 1975 design. Best yet, it features the almost identical size of 52.4mm, allowing for greater legibility and a truthful wearing experience just like back in the 70s. The faithful re-creation continues a legless silhouette with a measuring length of 53.5mm and a height of 17.2mm. The case back of this dive watch bears the same Seiko Tsunami emblem just as the 6159-7010 diver. The engravings commemorate the timeless style of this original timepiece and marks the 55th anniversary of Seiko’s, and Japan’s first saturation dive watch.
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| Ceramic Shroud. Monobloc construction. 1000m water resistant. |
Seiko’s Prospex lines are characterised by the “X” logo, which is applied here onto the bottom dial of the SBDX038, instead of the “Marinemaster” text found on the previous SBDX014 version. This new design is synonymous and found within the collection, and on other elite dive watches, like the SBDX023 and the upscaled SBDB027. The SBDX038 flaunts a deep matte black dial with its signature 1975 silver brushed handset that is unique to Seiko’s Tuna line-up, while tributing a clean design of the 1975 and 78 Tuna divers. Capturing the resplendent beauty of two-tone, these cool rose-gold accent hints at the timepiece’s superb functionality, even in the dark depths of the ocean.Furthermore. its handset, bezel markings and dial markers are applied with long-lasting Lumibrite which has an ivory green hue under normal lighting conditions and glows green in the dark, allowing for excellent readability.
Now with a screw-down sterile crown as well as a date display both located at its 4 and 3 o’clock respectively, this diver has a water resistance of 1000m, which is pumped up from 600m that the 7549 has. The sleek font style and format of its dial reflect the exact essence of the classic 60s-70s design. Additionally, this timepiece is fitted with a flat sapphire crystal which graces the watch with a utilitarian look.
The SBDX038 comes with a black rubber strap that complements the ocean blue hue of its dial. Matching the dive watch perfectly, the athletic look of this silicon rubber strap comes from its unique accordion patterns.
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| Seiko's Lumibrite needs no introduction |
This timepiece is the epitome of Seiko’s dive watches and one of the best recreations of the original 1975 6159-7010 diver. With only limited pieces produced annually, this dive watch is a much-anticipated addition to the Prospex collection. This well fabricated timepiece is the ultimate expression of the first golden Tuna, and is fully up to date in its specifications and execution which is testament to Seiko’s high standards and customer-centric ethos. Presenting the SBDX038, a maxed-out specs diver honouring Seiko’s effort in dive watch history that will find its way into the collections of many dive watch enthusiasts and elite collectors.
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