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”.
Marine Master Violet Tuna - Ltd Ed. 800pcs - Ref. SBBN042 / S23627J1
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.
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.
Titanium “Inner-Case” and Violet Ceramic “Outer Protector”
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 Seiko Marine Master Violet Tuna - Ltd Ed. 800pcs - Ref. SBBN042 / S23627J1 is Limited Edition to 800 pieces worldwide that is derived from the classic model, the Marine Master Pro. 1000M "Darth" Tuna Ref. SBBN025. Seiko have placed their top end quartz caliber into the new model. The high-tech 7C46 is a 7 jeweled movement, featuring hi-torque tolerances and efficiency, that enables the gears and pinions to move and turn the handset in perfect sync with the energy-pulse, needing lesser kinetic effort via electronic step motors that power them.
High-tech 7C46 movement, featuring hi-torque tolerances and efficiency
The Marine Master Violet Tuna - Ltd Ed. 800pcs - Ref. SBBN042 / S23627J1 stays true to the original tuna, where its case size and dial aesthetics were clearly emulated. It carries the robust titanium with super-hard coating with a violet ceramic outer shroud thus the nickname. The violet tuna has a dimension at 49.4mm wide and 15.3mm tall. This wears as close to its current brethren, the SBBN025 and SBX014 Emperor Tuna, that features the same 1000m water resistance.
The 49.4mm titanium case is treated with a black super-hard coating. Due to the lack of lugs in the Tuna design, the case is only 49.4mm lugs to lugs. That means this "Tuna" sits so comfortably on the wrist. In fact we think it fits more like a conventional 42mm watch with lugs. The 49.4mm case is constructed out of 2 layers, inner and outer case. The inner case is made of titanium and of a monobloc construction. Without a need for a screwdown caseback, the movement is cased from the top, before the dial and the crystal. This allows the watch to be water resistant to 1000m (in fact, it reached 3.000m affixed to the exterior hull of KAIKO 7000 II, a remotely operated undersea research vehicle) and to be fully impermeable to helium.
All in the details
The Marine Master Violet Tuna - Ltd Ed. 800pcs - Ref. SBBN042 / S23627J1 dial design is also faithful to the original. Designed with large luminous dots, batons and triangular indexes like the original Tunas and large luminous hands. Both the hands and the indexes are coated with a warm cream colour that matches the idea of a vintage re-issue and that perfectly mixes with the violet protective shroud. The dial's makers and hands are treated with Seiko's Lumibrite for awesome low light visibility. There's a lot of lume on this Tuna. Like a ton of it. Probably, the most we've ever seen on a watch.
Seiko's Lumibrite needs no introduction
To sum it all up, the new Marine Master Violet Tuna - Ltd Ed. 800pcs - Ref. SBBN042 / S23627J1 is quite the watch to own to complete the Marine Master Tuna collection. It is probably one of the most exciting colorway from the Tuna collection. If you want a Marine Master Tuna and dislike the conventional black and steel models, this is the model to go for. In time to come, it will join the ranks of the original Marine Master Tuna, the SBBN025, SBDX013 and SBDX014. It will not just being an iconic dive watch today, and also a true collector piece, produced solely from the land of the rising sun.