Seiko Digital Tuna Review (SBEP003): Field Testing the Fieldmaster

In the world of rugged digital watches the Casio G-Shock reigns supreme. It’s the undisputed champ. The variety of G-Shocks is mind blowing. But what if you’re not on-board? I happen to be in that camp. I don’t have any discontent with G-Shocks. There is just a disconnect. I’ve never been able to find a G-Shock that was a great match for me.

Enter the Seiko SBEP003 Fieldmaster, the “Digi Tuna”. It’s technically a JDM (Japanese Domestic Model). Well, sort of. I’ve seen the SBEP003 Seiko Digital Tuna briefly on the Seiko USA website and some other US online retailer sites as well. I grew intrigued about this oddity and had to know more.

I was sitting at my desk at the office when I received an alert from our home doorbell cam. I swiped and saw my wife signing for a package. I played it cool and waited. It was the longest thirty minutes in recent history. I casually texted her, “Who was at the door?”

She replied, “Some package came for you from Japan”. Silent fist pump. The TBWS mothership had hooked it up!

The Case:

Let the dimensions fool you. It’s OK. Yes, on a spec sheet the 49.5mm case would be a turn-off to most. Me included! I was like, “OK… maybe they balanced it with a super low height and a short lug to lug.” Nope, it’s 14.3mm tall and the lug to lug is 49.5mm. How do they make this formula work for anyone besides Aaron Judge?

The answer was easy. The market was right for the Digital Tuna to be aesthetically accepted. Wearable technology is everywhere. Many common pieces of wearable technology (don’t call it a smart watch) are similar in size such as your average Suunto or Garmin. People who are into wearable technology are really into it. They tend to wear them to the office and out to dinner, not just on their daily jog. A big hunk of plastic on the wrist is not an uncommon sight anymore. To be accepted alongside the Suuntos and Garmins, the watch has to have “the look”.

The most distinguishing feature of the Seiko SBEP003 Digital Tuna is the shroud that surrounds the case and the bezel. The shape turns the watch into a flat cylinder, like a can of tuna fish, hence the nickname “tuna”. The shroud is made of the same resin as the rest of the case. That gives it a satin black finish that is almost flat. That’s important. The black color helps the watch seem smaller than it actually is. The white version, reference SBEP011 will appear larger than the black models.

Despite being almost 50mm, the Seiko Digital Tuna weighs only 80g. If you’re used to a steel mechanical watch on a steel bracelet, you could easily forget that you’re wearing it. The weight also plays into the size being deceptive.

The Dial and Bezel:

Seiko used Japanese design firm Lowercase as design consultants. That was an ironic partnership because there is not a single lowercase letter on the entire watch. I’m not sure if it was Seiko’s or Lowercase’s decision, but one of my favorite elements is that space is economized on the top side of the watch.

The dial of the SBEP003 packs a lot of information. Between the digital display and the bezel insert lies the solar panel. Casio G-Shocks that are solar powered hide the panel similarly. However, the circular panel on the SBEP003 blends perfectly into the Seiko.

Information on the digital tuna display is on overload. When in main time-telling mode you get: the time, a second time zone, the day, the date, the seconds, the sound indicator, the battery reserve, the stopwatch if running, and the minutes along the outside of the dial. It’s a lot, but it’s still easy to read the time at a glance. There are a few complaints about needing to “tap” the face to get the backlight to operate, but I had no issues with it.

This was my first friction bezel. I was apprehensive at first, but it was secure. There is definitely an art to rotating it easily. You have to apply pressure at the just the right angle. The pip is the only lumed part of the watch.

The blue and red “Pepsi” colored bezel insert is a slightly different shade than SKXs and Turtles that you’re used to. Think a little darker, like Tudor’s “Burgundy and Blue”. The actual bezel itself is only 43mm in diameter. That gives you an idea of how much the shroud adds. What if the shroud wasn’t there? Would you feel the same way about the watch? I think that it would be a little less special.

The Movement:

The Digital Tuna is powered by the Seiko caliber S802. The solar portion that keeps it charged is the Seiko V147. There is no battery to change. The SBEP003 can keep running for five months when fully charged. There is also a power save mode that will allow the watch to go into hibernation when not in use. This will extend the charge to 20 months. A little tap will wake it up. Battery replacement has to be done by Seiko. Luckily the batteries in these movements can last 60-70 years.

There are no jewels to count or decorative “Geneve finishing” displayed through the case back. For the Seiko SBEP003 it’s all digital and the function is what counts. I’m a duathlete. A Duathlon is like a Triathlon without the swimming component. (Run / Bike / Run) I always train with a watch. I also spend a large amount of my time in the summer in the water. How does this watch’s functionality perform form in each of these elements?

· Running:

My sister-in-law uses an entry-level Garmin for endurance running. It tracks her pace and alerts her to speed up or slow down. I like to be a little less connected. Time is still a good lead and lag indicator of how you are doing. The Seiko SBEP003 has every stopwatch feature that you need running. I never recalled specific laps or broke out a split, but the functionality is available. Elapsed time was good enough for me.

The best part of running with the Seiko SBEP003 was the weight, or lack thereof. If you are used to running with a mechanical watch, you know that at some point the weight of the watch will start pulling on your arm like a brick. As you sweat it only gets worse as it slides around. Not with the Digital Tuna.

· Cycling:

I’ve spent the majority of time cycling with a traditional dive watch. My routine on early morning rides is to pick a 45-50 minute route to be back home by 6:00am to shower and get ready for work. With a traditional dive watch, I use the bezel to measure elapsed time and the hour and minute hands to let me know when I need to be home.

With the Seiko SBEP003 it was a bit of an adjustment switching to the stopwatch feature. I could measure elapsed time more accurately. I could also measure lips and “splits” if I wanted to run after finishing my cycling routine. The problem that I had was the minute hashmarks around the outside disappear with the stopwatch feature and make the bezel useless. The actual time also shrinks to such a small size that it’s nearly impossible to read at 18.5mph.

· Swimming:

I don’t do any competitive swimming. However, I do spend a lot of time in the water. Despite being rated for 20BAR, the Digital Tuna does not meet the ISO 6425 standard to be a dive watch. I don’t really care, there is more than enough water resistance for pool and beach activities. The worst thing that could happen to me with the bidirectional bezel is saying, “Kids! Five more minutes and you have to get out of the pool!”, and it turning into an idle threat because I mistakenly added more time.

I was confident and secure with it at the beach. Buried in the sand or paddle boarding in on the surf, the SBEP003 was right at home in the ocean. I never held back. Seiko should call it the “Oceanmaster”.

The Strap:

Oh how I love a good Seiko fanned (accordion) silicone strap. It should be noted that not all Seiko straps of this design are created equal. The one that comes on the SKX is junk. The ones what come on the Samurai and Baby Marine Master are fantastic. The black 22mm strap that comes with the Seiko Digital Tuna is equally awesome, maybe better.

The strap is 132mm + 77mm in length. That puts the tail right up to the fan on my 6.75” wrist. The big difference is the black buckle and the silicone keeper. Both the Samurai and Baby Marine Master have an oversized buckle with a metal keeper. I have to add an additional rubber keeper on both. The SBEP003’s larger rubber keeper works better in its standalone stock form. I have yet to encounter someone that thinks this silicone strap isn’t comfortable. There are two negatives with the strap. The first is that the fanned portion makes it difficult to sleeve under a cuff. The other is that black silicone straps can be lint magnets. I’ve scrubbed a lot of sunscreen off of this one using a little dish soap with ease.

Final Thoughts:

Is it easy to tell time? Yes.

Could I #watchfast it? Yes.

When it comes down to the features, the Seiko SBEP003 Digital Tuna could be your diver / driver / flyer all in one. It has a rotating bezel and 20 BAR water resistance. There is a complicated stopwatch timing feature. And just for a little icing on the cake, you can easily jump between multiple time zones with the push of one button. No flyer vs caller GMT debate here. This is a grab and go watch in the truest form.

If I had to pick one “Apocalypse Watch”, the Seiko SBEP003 would be it. More realistically, if I was going to donate watches to a village in a third world country I would also pick the Digital Tuna. In either scenario I’d feel confident that the watch would continually work for decades without needing repairs or battery replacements.

The Seiko SNJ027 “Arnie” reissue might have gotten all the press this year. Unlike the Arnie, you don’t have to yell, ”Get to-da chopp-aah!”, every time you leave the grocery store. That is something your significant other will definitely appreciate.

Like most Seikos, there are a few design choices that make me scratch my head, but overall it’s a solid choice. The Digital Tuna is a sleeper piece for the enthusiast who wants to diversify their collection with the added security of a familiar Seiko “Pepsi” bezel. Pick-up a Digital Tuna from Amazon if you can and put it through something rugged — you’ll feel better for doing it.