Seiko Prospex Sumo Automatic Diver SPB101J1
The Seiko SPB101J1 (SBDC083 ), also known as the Seiko Sumo, is perhaps one of the greatest entry-level sports watches and one of the better built-in Seikos line-up for the money. In 2019 Seiko finally updated their Sumo models giving them a slightly different and refined look, but perhaps most important an in-house improved movement Caliber 6R35.
At a price of around $800, you get a fully in-house built Seiko Prospex, which is Seiko’s standard for a professional watch. Don’t let the price point fool you as this might be one of the best in-house built watches for the money at the market. In our opinion, it is one of the dive watches at this price point that offers the best value for money.
The Seiko Sumo is also known as the MM200, which stands for ”Marinemaster 200” because of the similarities with the much more expensive SLA021J1 known as the real MarineMaster ”MM300”. This truly is a great watch for the money and is a perfect entry-level professional Divers watch, Let’s have a deeper understanding of why that is so, and go into detail about the Seiko Prospex Sumo SPB101J1 Automatic Watch.
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Dial
The dial of the Seiko SPB101J1 is slightly matte which gives it a textured and rich finish and also prevents glare and distracting reflections. The dial has not changed very much from the predecessor as the text is the same, the date window still has the white squared line around it and the Prospex logo still is present. The dial is however richly filled with luminova, or as Seiko calls it “LumiBrite”, which really does glow brightly in the dark.
The recognizable look of the Sumo is still present on the dial with the iconic index mark at 12 o’clock. The date is placed at the 3 o’clock position and triangle indexes without the tip at 6 and 9 o’clock. One major difference if you purchase the SPB101J1 which is made for the market worldwide, or the SBDC083 which is made for the Japanese market, is the text placed at 6 o’clock. On the SBDC083 ”Japan 6R35-” and ”OCAO R 2” is written at the bottom of the dial, which the SPB101J1 does not have. Apart from that, they are identical.
Hands
The hands are updated with a triangled minute and hour hand which is more suitable for the Sumo and enriches the impression and personality of the Sumo. All hands have plenty of LumiBrite and have a great contrast of the dial making it easy to tell the time.
Case
The case, just like when the Sumo got released in 2007, is still bulky and is meant to have a large and sporty profile. Although the size of 45mm might scare you, the lugs are relatively short with a lug-to-lug size of 52.5MM making it quite wearable without it looking awkward on smaller wrists. The case measures 13,5mm in height, but again makes an overall great appearance on the wrist. The case is made out of stainless steel with a brushed and polished finish. The iconic lugs, and perhaps Seiko’s trademark with the screw-down-crown placed at 4 o’clock really make this watch instantly recognizable as a Seiko.
The watch is equipped with a sapphire crystal, making it extremely durable in rough conditions, and with a water resistance of 200M, you won’t have to worry about using your watch in water. Although the water resistance is told to be 200M, Seiko always tests their watches to see if they can handle more pressure than they are made for, which is done by always testing 25% more than what is specified. With that said, inofficially the case is 250M water-resistant. The lugs are 20mm, which is one of the most common sizes for watch straps, and with the drilled holes on the side, it is easy to remove and change straps and bracelets on it. The drilled lugs also contribute to giving the watch a more tool-like appearance which really enriches the tool-like look.
The screw-down case back has the iconic Seiko Tsunami emblem which can be seen on most Seiko watches Prospex watches.
Bracelet
The Seiko SPB101J1 has a sporty and robust stainless steel 3-piece-bracelet with a width of 20mm with brushed links and polished accents. The bracelet also has a wet-suit extension that offers a large enough extension to be used for putting the watch over your wetsuit. The bracelet really gives the overall impression of the Sumo a seamless look and feel. On the wrist, it gives the impression that it will never let you down.
Bezel
With a coin-edged bezel and an insert made out of aluminum, the first obvious difference when comparing with the previous Sumo models is the new fat font on the bezel with sleeker numerals with great legibility. The bezel has a 60-minute marking and a 120-click uni-directional bezel. The bezel operates smoothly when rotating it.
Movement
The movement is perhaps the biggest difference going from Seiko’s 14-year-old 6R15 to the new in-house caliber 6R35. The movement is automatic with a central rotor and offers a power reserve of 70 hours, which is a huge improvement of 20 hours from the 6R15. This robust and durable movement gives makes this Seiko SPB101J1 a great watch in this price class. The movement beats at a 3Hz frequency making 21.600 beats per hour.
Furthermore, the watch has a hacking feature that stops the second hand from ticking when pulling out the crown to set the time which allows for more accurate time-setting. The watch has a manual wound option which is great for starting the watch if it has run out of battery and stopped, a quick-date feature making it fast and easy to adjust to the correct date if the watch has been stopped and 24 jewels which are improved from the previous caliber making the movement made to handle heat and friction in a better and a more lasting way.
You can find this watch on Amazon
