There are many vintage Seiko divers popular with collectors, and the Seiko Marinemaster line easily counts itself among these legends – like full set, 2002 Seiko Marinemaster 300 Ref. SBDX001 diver here, with its original bracelet, boxes, and papers.
Without a doubt a tool watch, Seiko’s Marinemaster 300 was first launched in 2000 as a Japanese Domestic Market (JDM)-only dive watch – not until 2012 did the Japanese company release the watch in Europe. Given the Marinemaster was only sold for three years (Seiko ended the model in 2015) outside of Japan, it’s not often seen outside the country.
As noted, the Marinemaster shares a linage with 1960s Seiko dive legends, especially the iconic 6215-7000 and 6159-7000. Seiko made use of the hand and indice shapes, the large 44-mm monobloc case, and the crown at 4 o’clock. The fresh, retro design allows the SBDX001 to stand alone, away from the crowd of monotonous diving watches à la the Rolex Sub (yes, we said that).
The automatic movement Seiko chose for the Marinemaster 300, the state-of-the-art 8L35, is based on the Grand Seiko Calibre 9S55, a notable vote of confidence in the watch by Seiko. Due to the screw-down crown and monobloc case construction of the SBDX001, the watch was designed to be water-resistant to 300 meters (30 bar, 984 feet).
Seiko also designed the Marinemaster 300 to be suitable for saturation diving, despite the case not possessing a helium escape value. As the midsection and case back are a single, continuous unit (ie: monobloc), the SBDX001 design renders it far more difficult for helium molecules to enter the watch.
This Seiko Marinemaster diver comes on its original bracelet, nylon strap, rugged travel case, and springbar tool.
