Thursday, June 28, 2018

SEIKO Prospex Fieldmaster LOWERCASE SBEP001 "Digi Tuna" (similar to SBEP003, SBEP005, SBEP007 & SBEP009) - A Good Start by Seiko to Make a New Niche for Itself, A Review (plus Video)

Seiko is synonymous with the tuna-styled dive watches. It has become a genre on itself and a lot of people (especially professional divers) can vouch for their reliability and effectiveness to handle the extreme of situations. There have never been a fully digital Tuna before but this year, Seiko decided to spring five models under the new SBEP nomenclature.

Made in collaboration with the Japanese design consultants LOWERCASE, Seiko is able to bring something fresh and exciting to an otherwise  bland tuna styling that have not gone through much changes for decades. Lead by Mr. Yuki Kajiwara, creative director of LOWERCASE, the SBEP series amalgamate two important considerations by professional users - damage proof construction (the Tuna casing) and clear visual (digital display). This is not a breakthrough in concept though. There are other brands that already fulfilled this market space, for example Casio Protrek Frogman, but for Seikonstas, this is the first for Seiko.

The SBEP001 is also classified as a Fieldmaster. This nomenclature signifies the watch has been geared specifically for land explorers and adventurers. The ability to withstand 200 meters of water pressure also points to its flexibility to be used for recreational diving as well.

Since this is the first of the SBEP series, I decided to get the SBEP001 to grace the collection.

The Watch

In terms of dimensions, the SBEP001 is sizeable. This watch is 49.5 mm in diameter and coupled with Seiko's famous 'hidden' lug design (the short lugs are placed below the watch casing and angled steeply downwards), the lug-to-lug width is also 49.5 mm. This makes this watch visually obvious on the wrist yet easily wearable. The two piece watch casing design consisting of the main casing plus  the bezel shroud makes for a tall watch with a 14 mm height. As a tool watch, this should not be a problem as the size helps viewing the information on the dial much easier. Using it other than what it was intended for may cause problems for users. Case in point; it is definitely not suitable for formal wear.

The watch casing is made out of 316L stainless steel. Mostly ion coated black except for the pushers and the back-plate. The pushers are polished with crisscross pattern on the top surface for grip while the black-plate is brushed finish. The shroud is made out of a special plastic compound that has a high scratch proof capability. On closer inspection, it has a bakelite-like texture.

The back-plate is sealed to the watch casing via four screws. Apart from some basic information about the watch, Seiko also reprinted the functions of all four pushers in bold and highlighted.

Despite the SBEP001 being a full digital watch, it also comes with a bidirectional bezel. The bezel uses friction to stay put and marked with dot minute markers, line 5-minute markers and Arabic numeral 10-minute markers. The require illuminated pip is provided at the 12 o'clock position. More about the way it is used will be provided later.

There are four pushers on the SBEP001. Three on the left and one on the right. The main pusher to cycle through the functions on the watch is the one on the right. The other three pushers are to control the various functions chosen.

The watch is paired with an accordion-style silicon strap with buckle. However, there is a lack of brand signage. I expected to find a Seiko's standard strap with the brand printed at least on the underside of the strap, strap guide as well as a signed buckle. However, the strap is sterile and devoid of any other markings except for a small section close to the underside of the buckle.

Although Seiko did not mentioned it in the manual, I suspect the SBEP001 conformed at least to the ISO6425 dive watch standard (or better). The way the bezel is crafted as well the 20 Bar or 200 meter water rating for the watch all points to a serious dive watch. Moreover, the SBEP001 must have the necessary credibility for Seiko to put it as part of the Prospex line.

Seiko have been marketing heavily on LOWERCASE's contribution to this project. However, visually, apart from the watch box (see The Reveal), nothing about the collaboration can be seen on the watch itself. You can't find a small print or logo of LOWERCASE on the watch itself. Very strange collaboration indeed.

Functions of the Watch

Functions in the watch include: time & calendar function (including DST); dual time display function (including world time with 44 cities); stopwatch, timer & recall functions; solar monitor function; power safe & sleep functions; alarm function (3 separate channels); and a sound demonstration function. For more information on the functions, please refer to the manual attached below.

Seiko can squeeze in more functionality into the watch if it wants to. However, pricing consideration limits the level and number of complication so as not to out priced the watch away from the mass market. As it stands, the available functions in the SBEP001 looks very familiar to a typical Casio G-Shock. This could be a conscious decision by Seiko considering this is one market space that is totally dominated by Casio. Although Seiko does have a few ABC (altimeter, barometer & compass) watches (see Seiko Prospex Alpinist Solar Titanium Multi-Sensor as an example), it is just a drop in the ocean when compared to the many models made available by Casio. Seiko must have studied the demand and supply of Casio's various lines (from the cheapest to the most expensive); G-Shock, Protrek, MT-G and MR-G. Without a doubt, the G-Shock line generates the most sales and fan base. I believe Seiko is gunning for Casio's G-Shock dominance. This could be the opening salvo.

The controls for the various functions are the four pushers provided. Manipulating them while the watch is on the wrist is not a problem as the pushers are relatively big and easy to engage due to the checkered top surface.

The Dial

Permanent texts and logo on the dial are as follows: at the peripheral from 12 o'clock and clockwise - the brand name, "DUAL TIME", "MODE", "20 BAR", "⊖SET", "ADJUST" and "⊕SET". Going inwards from the edge of the dial, you will find the Prospex logo in the center of the upper quadrant.

The screen has a reversed display Nematic Liquid Crystal (the latest variation of the LCD screen) that has white display over black background. This has the benefit of reducing energy by reducing the number of items that needed to be highlighted. You will also see nine icons on the dial that represent the following: battery mark, power safe mark, sleep mark, stopwatch mark, timer mark, world time mark, DST mark, alarm mark and hourly time signal mark. See the picture below on the description of the various icons mentioned.

Powering the SBEP001 is a Seiko Solar Caliber S802 which has an operating time of approximately  5 months when fully charged and a power reserve of approximately 20 months. It is accurate to within ±20 seconds per month. This caliber has four unique features.

The first feature is the Tap Input function that allows users to switch on the back light by just tapping the screen instead of a dedicated button or pusher. This is the first time I've see a touchscreen been use by Seiko. Do note the tap function seems to work only when the watch is on a wrist. I tried to get it going when it was not worn but nothing happened. It only works when you wear it. I suspect there is a sensor near the case back. Not sure why Seiko put this 'blocking' feature into the design. Below are photos showing the screen unlighted and lighted.

Tissot has spearheaded this method of user interface for years now with their Tissot T-Touch line of quartz watches (see an example in my collection by clicking on this link). Although the interface for the SBEP001 is in no way as capable as the T-Touch, its a good start. Hopefully Seiko may want to take it to the next level in future projects.

The second feature is the digital minute markers moving in a circular path at the peripheral of the screen. This has the effect of mimicking the minutes hand. Hence, the use of a traditional bezel for this watch is possible.

The third feature is the Solar Monitor Mode which is part power reserve indicator as well as the level of power generated from the solar cells. The power reserve indicator is located at the bottom left peripheral of the dial between 7 o'clock and 11 o'clock. Here, dot markers representing 11 equal portions from 0% to 100% are shown. Meanwhile, the power generation level is also indicated by dot markers for 11 levels from 00 to 10 between the 5 o'clock and 1 o'clock. Apart from the markers, a number value is also provided in the middle of the screen.

The fourth and final feature is the Contrast Function. One of the general feedback people have on reversed display digital screens is the difficulty of reading the information. Seiko decided to give the option to users to control the contrast of the display. For the first time, a contrast function has been added to give that choice to the consumers.

The Wearing Experience

The watch wears like any Seiko Tuna although at just 80 grams, it is lighter than most Tunas. This makes it easier to wear for a longer period. Despite it size, its is deceptively easy to wield on the wrist. Definitely a comfortable watch to wear.

The complications provided on the watch is useful but adding an ABC (or part thereof) would be better.

The biggest issue I have is the overall construction itself. As a Seiko Tuna, it should be indestructible. However, on closer inspection, my expectation was dashed. It looks fine but it feels cheap and I just can't see it going head-to-head with a Casio G-Shock. The use of plastic for the shroud was a major letdown. Although one would argue that most G-Shocks are plastic anyway, a G-Shock does not have any preconceive icon to compare them against apart from another G-Shock which is also made out of plastic. For the SBEP001, it has been given the nickname of "Digi Tuna" which makes the comparable icon to another Seiko Tuna in the form of the Emperor Tuna. Here is where it fails miserably as the concept of a Tuna's indestructibility is not confidently reflected on the SBEP001. Moreover, by classifying the watch as part of the Prospex line makes that linkage even more obvious.

To me, this watch should not be classified under the Prospex line. It should perhaps be clustered under a different line instead.

If you disregard this perception issue, the watch is a capable little package with all the necessary functionalities required by a typical person. Having said that, it can compete head on with the likes of the Casio G-Shock GW-M5610BC-1JF for example. I believe it can take a bashing but Seiko have not published any tests done to the watch on that front. I can only assume it is capable of taking similar level of punishment of a G-Shock purely on the fact it's listed as a Prospex. At the moment it is only conjecture. Marketing wise, Seiko need to answer this question so that it would allay any doubts and concerns consumers have.

Another issue I have is the bidirectional bezel. It is designed more like a Marinemaster instead of a Fieldmaster. A cursory look will cause anyone to come to the wrong conclusion that the watch is a diver when it is clearly not. If you look at the various models of Fieldmasters or even Landmasters from Seiko, every single one of them (apart from the design collaboration with LOWERCASE) have either world-timer marked bezel or compass marked bezel. Moreover, the bidirectional bezel is a dead giveaway that it is not a diver. In my opinion, a countdown bezel would be more appropriate for this watch instead. Seiko should have insisted during the design phase. As it is, this series has created some confusion with fans (myself included).

The final issue I have with this watch is the strap provided. The standard accordion silicon strap of the SBEP001 is generally provided to dive watches which further confuses the true purpose of this watch. Moreover, the accordion section of the strap is too 'bunchy' for my taste. A simple strap would have been sufficient.

Having said all that, one redeeming feature of the watch that is not found in a G-Shock is its ability to changes straps readily like a common wristwatch. Whereas a G-Shock would need adapters to enable it to attach normal watch straps, you can do it immediately with the SBEP001 straight from the box. You can customize it anyway you like. Personally, a brown leather or canvas strap matches the black casing beautifully.


A good start by Seiko to make a new niche for itself. Although it appears to stumble a bit in terms of perception, it can be remedied without much effort by Seiko. Perhaps it would be best to take full control of the design work from now on. Honestly, I am still pleased to get the watch and I can't wait for new projects under this particular branch of Seiko watches.

Purchase Price

I bought the watch via SeiyaJapan. The merchant charged me USD294.00 or RM1,213.75. Due to the abolishment of the GST sales tax in  Malaysia, the package from Japan was not quarantined by customs and it was delivered directly to me.

The Reveal

This is the first watch I bought from Japan after the abolishment of GST in Malaysia. As expected, instead of being held at customs, the package was duly delivered to the appointed address without much delay and additional costs.

SeiyaJapan also gave a free polishing cloth and the 2018 Seiko Brochure with the purchase. Truly appreciated the gesture.

The package came in two parts, the outer black cardboard packaging box with the brand, product line and logo printed prominently in silver on the top. I was also surprised to see the guarantee document is separate from this. Seiko had to keep them separated because the box is not big enough to also include the guarantee document.

Opening this box you find inside a very thick manual as well as the main watch box. The main watch box is a more solid cardboard box. It is also similarly printed like the outer box accept it has additionally, on the front surface at the top corner, the brand and logo of LOWERCASE.

In all the previous watch reveals, the SBEP001 is by far the watch with the most tags - there's four of them.

The Series

The SBEP is a new range of the Fieldmaster series which is part of the Prospex line under Seiko. There are five models in this range where the first three are standard models and the last two are limited edition timepieces. All these models are made in China.




As you can see, the differences in the first standard production models stems from the bezel and pusher colours. Price wise, the SBEP001 is slightly cheaper.

The last two are limited edition pieces. The SBEP007 model is limited to 600 units sold through Journal Standard shops, and SBEP009 model is limited to 300 units sold through Urban Research shops in Japan. For these pieces, a special case-back is provided.

SBEP07 (front)

SBEP07 (back)
600 units only

SBEP09 (front)

SBEP09 (back)
300 units only


Driving system: Solar
Caliber Number: S802
Band material: Silicon
Glass: Glass
Operating duration: Approximately 5 months (when fully charged)
Power saving: Approximately 20 months
Accuracy: ±20 seconds per month
Water resistance: 20 bar water resistance
Size: H49.9mm x W49.5mm x D14.1mm
The perimeter of bracelet: 210mm
Weight: 80g
Driving system:

  • Rotating bezel
  • Case back with 4 screws
  • Power save
  • Alarm function (three-channel daily alarm)
  • Timer function
  • World time function (44 cities)
  • Dual-time
  • Sound demonstration function

Manual Seiko Prospex SBEP001 (Caliber S802) (English from page 65 onwards)

Comparing Against the Emperor Tuna

Here are some photos of the SBEP001 with the Emperor Tuna (on the left in the photo below). As you can see, size wise, they are comparable.

The lugs are slightly different. The SBEP001 is slightly less taller than the Emperor Tuna.

Photo Gallery


  1. Hey buddy, U must be the 2nd person in Malaysia to have this after me.

  2. Hi, the light on my my 003 came on without it being on my wrist. Anyway, thanks for the detailed writeup.

  3. Great article with excellent idea!Thank you for such a valuable article. I really appreciate for this great information..



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