Seiko Marinemaster

Models from the Seiko Marinemaster collection are professional diving watches that are reliable even under extreme conditions. Top models from the series are water-resistant to 1,000 m (100 bar, 3,281 ft), making them ideal for the professional diver. In 2014, the Marinemaster Professional 1000M plunged to 3,000 meters below sea level attached to the outside of an unmanned research vessel and was fully functional upon resurfacing.

These watches feature massive cases, highly legible dials, bright luminous hands and indices, and a crown at 4 o'clock. The Japanese manufacturer Seiko equips the timepieces with high-precision Spring Drive movements or robust automatic calibers such as the 8L35 – calibers that are both reliable and durable.

Especially popular are the line's classic models with a black dial and bezel, like the references SBDX001 and SBDX017. These and other Marinemaster variants have a monobloc case, which means the case back is hermetically sealed. This form of construction prevents helium from seeping into the case, making the watch suitable for saturation diving.

Prices for a standard issue Seiko Marinemaster in mint condition start at about 2,200 USD for the ref. SBDX001, and climb to around 3,300 USD for a titanium Marinemaster Professional 600M Spring Drive. Special editions are particularly attractive to Seiko collectors and enthusiasts. The Prospex Marinemaster 300M Limited Edition ref. SBDX012, limited to just 1,000 pieces, changes hands for approximately 5,400 USD in mint condition.

Even rarer is the Marinemaster Professional 1000M Diver's Hi-Beat model with the reference number SBEX001, powered by the in-house caliber 8L55. Limited to just 700 pieces, this titanium watch demands an investment of roughly 5,300 USD in good condition. The SLA015 features a blue dial and is limited to a mere 200 pieces. This watch will set you back at least 7,500 USD.

Watches in the Seiko Marinemaster 300 series are an excellent entry-point into the Marinemaster collection. Visually, these timepieces, with their cushion-shaped, 44-mm stainless steel cases and a crown at 4 o'clock, are reminiscent of the well-known and much-loved Seiko Sumo.

The basic design of the dial and bezel largely resembles that of a classic diving watch (think: Rolex Submariner), but is nevertheless immediately recognizable as a Seiko. The black, glossy dial features large, luminous dot indices interrupted by a date display at 3 o'clock, single bar indices at 6 and 9, and a double bar index at 12 reminiscent of the shape of an open book. Inside the timepiece, you'll find the high-quality in-house Seiko caliber 8L35, which boasts a 50-hour power reserve.

The Marinemaster 300 features an especially robust monobloc case, which can only be opened from the front. This means that if you need to get the watch serviced, the watchmaker can only access the movement by removing the bezel, crystal, dial, and hands. For the crystal, the Japanese manufacturer employs a proprietary material, Hardlex, which has a hardness between that of conventional mineral and sapphire crystals. The Marinemaster 300 comes on a three-piece link stainless steel bracelet, the clasp of which allows for fine adjustments and comes with a diving extension. Seiko also includes a black rubber waffle strap.

The reference SBDX017 is a slightly revamped version of the SBDX001. While its predecessor costs about 2,900 USD new, you can call the SBDX017 yours for an additional 200 USD.

If you need your diving watch to have more water resistance than 300 m (30 bar, 984 ft), take a look at the Marinemaster Professional 1000M. As its name suggests, this professional diving watch is water-resistant to 1,000 m (100 bar, 3,281 ft). In 2014, the watch even dived to 3,000 m strapped to the outside of an unmanned research vessel. This kind of resistance to pressure calls for a massive, robust case: the Marinemaster 1000M with the reference number SBDX013 is 48 mm in diameter and 17 mm thick. The large case looks like a can of tuna, which led to the watch's nickname, “Tuna.”

Even though the timepiece isn't exactly suited to everyday use, it enjoys immense popularity among Seiko fans. The SBDX013 has a titanium case with black titanium carbide plating, making it even more durable. The watch comes on a flexible silicon strap and is equipeed with the caliber 8L35, which also powers the Marinemaster 300M and boasts a power reserve of 50 hours. The daily deviation is between +15 and -10 seconds, and is thus not quite on the same level as a standard Swiss chronometer. Seiko uses its proprietary luminescent material LumiBrite on the hands and indices, making them easily legible in the dark.

If the overall black design isn't to your taste, the Marinemaster Professional 1000M with the reference number SBDX014 might be more your style. From a technical standpoint, this model is identical to the ref. SBDX013, but visually, its rose gold-plated components make the watch stand out. Unlike the Marinemaster 300, Seiko uses a sapphire crystal on refs. SBDX014 and SBDX013 to protect the displays from external influences. In mint condition, these two references change hands for between 2,400 EUR and 2,600 EUR on Chrono24.

The Seiko Marinemaster model with the reference number SBDB011 features the Seiko-developed and patented Spring Drive technology. The 45-mm titanium watch is powered by the caliber 5R66, which comes with a 72-hour power reserve and a second time zone function.

The SBDB011 features a black bezel and dial, and the design is in keeping with the classic Seiko Marinemaster style. A sapphire crystal keeps water from entering the watch and damaging the dial and movement. You can tell whether the watch has Spring Drive technology by the corresponding inscription above 6 o'clock and the power reserve indicator at 8. The timepiece also comes with a second time zone, indicated by a second central hour hand and a 24-hour scale around the outer edge of the dial.

The three-piece link titanium bracelet comes with a fold-over safety clasp that allows for fine adjustments and a diving extension. You can call a mint condition model yours for approximately 3,300 USD on Chrono24.

Some Marinemaster models are limited in number. The reference SBDX012 was released in conjunction with the 50th anniversary of Seiko's Prospex collection and limited to just 1,000 pieces. The watch is essentially identical to the Marinemaster 300 ref. SBDX001 in terms of technology and design and is similarly powered by the caliber 8L35. The most noticeable differences are the gold accents on the watch's hands, indices, inscriptions, and diving scale. This timepiece demands an investment of around 5,400 USD on Chrono24.

The Marinemaster ref. SBEX001 is water-resistant to 1,000 m (100 bar, 3,281 ft) and powered by the automatic Hi-Beat caliber 8L55. The movement runs at 36,000 vph and boasts a 55-hour power reserve. The dial and bezel on this variant are black, and the dial features the characteristic applied dot and bar indices. Atypical of Marinemaster models, the date display on this timepiece is located at 3 o'clock. The SBEX001 comes on a stainless steel bracelet and costs about 5,500 USD.

The Marinemaster SLA015 is probably the most unusual version in the entire line, visually speaking. It's the only Marinemaster to feature a turquoise-blue dial with a sunburst finish. Furthermore, the collection's almost obligatory dot indices have been replaced by bar indices. Technically, the watch offers the same automatic caliber 8L35 used in refs. SBDX001 and SBDX017. The watch's monobloc case, which is water-resistant to 300 m (30 bar, 984 ft), and its three-piece link stainless steel bracelet are the same as those of the well-known standard editions. The SLA015, however, is limited to just 200 pieces. You can call this watch your own for approximately 7,500 USD.