Seiko Prospex SBDC003 Scuba 200m Blue Sumo - Although The Watch Is Not Perfect, It Can Stand On Its Own, A Review

This model was first launched in 2007. Back then, the design philosophy was very tool-like. This new design is a new development of the Seiko diving watch line where styling also becomes a design criteria. A new caliber has also been earmarked for use with this new model.

Codename "Sumo", it is one of the desirable watches that came out of the Seiko stable. When I got the opportunity to get it via my trusted Japanese supplier Katsu-san, I immediately ordered one and it promptly landed on my table.

The blue dial is what attracts me. Its ocean blue color is very consistent with the purpose of the watch and offers great readability. I loved the classic simplicity of the dial design. The markers are slightly raised with gives a 3 dimensional feel to it.

One of the striking visual cues on the watch is the relatively large width of the bezel. The additional space available on the bezel allows larger than normal Arabic numerals to be etched on it. The bezel is uni-directional with a lumed pip at the 0/60 minute position. It has a 120-click movement to complete one rotation.



The watch casing is another interesting area to focus on. In the photo below, the sides of the watch gradually increase in height thus shrouding ever so subtly the large bezel. This aspect is so subtle that only with close scrutiny would you able to see it.

I really appreciate that drilled-through spring-bar holes are standard on this watch. This greatly speeds up the strap changing process. Below is another angle of the watch that shows how the semi-shroud helps reduce the visual effect of the thick watch.

Although by just looking at the specifications we know that watch is big, but surprisingly, it looks much smaller. This is largely due to lugs that curve both inward and downward; a bezel whose insert slopes down away from the crystal; and a 20mm bracelet. The photo below helps show you have this feat was achieved. Seiko's designers was able to use these design tricks to reduce the watch's bulk.

The amount of lumibrite paint on the hands and markers is just amazing. The lume shine bright the whole night if given a good dose of light energy for it to absorb. The only issue I have with the dial is the replacement of the marker at the 3 o'clock position for a date window. Seiko shouldn't have done that. It breaks the symmetry of the dial, especially when viewed in the dark (see last photo). Seiko should have put the date window somewhere else.

Another comment a lot of people mentioned is the shape of the marker for the 12 o'clock position. Some say it looks like the female genitalia. There is no reason for Seiko to do that since the shape of the marker is already different and unique anyway. There must be a private joke between the designers.

On the solid screw-down case-back, only a small portion, near the center, is the etching of the famous tsunami logo. I would expect it to be slightly bigger.

In 2007, when this model was launched, Seiko also launched a new series of automatic caliber to replace the legendary 7S26 movement. Major improvements, such as hand-winding and hacking of the second hand are now available  The 6R15 is also equipped with a rapid date adjustment mechanism. With such a marriage, the SBDC003 is in a league of its own.

Using a main spring made of Spron 510, a material patented by Seiko and based on the Spring Drive technology, it is capable of maintaining a power reserve of 50 hours. Operating at a frequency of 21,600 alternations per hour, it is ultra sensitive and its can come alive almost instantaneously with a few shakes of the watch.

The deployant clasp with the diver extension unit clearly seen above the spring loaded flip-lock.


I guess the 20 mm bracelet is sufficient for this design. However, for me, a serious dive watch should have a minimum of 22 mm to be taken seriously. I do like the solid end-links and adjustment points running the entire length of the bracelet. However,  the clasp, a standard Seiko spring loaded flip-lock with a flip type wet suit extension, should have be redesigned as well. To make this watch truly special, this part shouldn't be the same as less expensive Seikos.

The screw-down crown as a nice deep initial on top of it. Engaging the threads when screwing down is not as smooth as Swiss watches. Not sure if that is a fair comment though.

In the photo below, noticed how thin the bracelets are? They are actually thinner than the Seiko Monsters'.

Love the curves on the watch casing.

The divers extension deployed. Gives an additional 0.75 inch to the bracelet.

The lume on the watch. Note the missing market at the 3 o'clock makes it look asymmetrical. I don't like that.

Watch Specification:
Brand: Seiko
Model name: Scuba 200 Sumo SBDC003
Reference number: SBDC003
Case material: Stainless Steel
Case diameter (without crown): 44.88 mm
Case diameter (crown included): 49.09 mm (10h - 4h)
Movement type: Automatic
Calibre: 6R15

Functions: Second, Minute, Hour,Date
Crystal: Hardlex (hardened mineral glass)
Power reserve: 50 hours

Lug width: 20.45 mm
Length from lug to lug: 52.21 mm
Case thickness: 13.73 mm
Water resistant: 200 m
Strap material: Stainless Steel Bracelet
Clasp type: Deployant clasp

Total weight: 170 grams

Overall, an excellent watch. It is a solid and classy. The blue is striking. Although the watch is not perfect, it can stand on its own.

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