Seiko Tuna Marine Master SBBN025 Review & Complete Guide
There are dive watches, and there are dive watches.
This type of watch has become immensely popular within the watch space. The dive watch design has become iconic, appreciated, and instantly recognizable with its distinct traits such as the unidirectional rotating bezel, large hour markers, large hands, and sporty profile.
Because of this, a wide array of manufacturers have jumped into the dive watch trend, which has now become more than just a trend and presented their own takes on this concept.
But not all divers are created equal. In fact, quite the opposite actually. Some manufacturers take the iconic design features and put them in a watch that doesn’t have the specifications to back it up. And this is of course completely fine considering the fact that the vast majority of people never come anywhere close to water.
However, if we are going to go further than that, a dive watch needs to have a water resistance of at least 200m.
It’s safe to say that the Rolex Submariner is the most iconic dive watch ever made. It has established an iconic status, instantly recognized by both watch enthusiasts and those who don’t care much about watches.
But does every ”dive watch” need to look like a Submariner? Seiko thinks not. And in a world where many divers look very similar to each other, Seiko has released refreshing takes on the dive watch that are unique, and distinct, yet do not compromise on build quality and reliability.
One of those watches is the Seiko Tuna Marine Master SBBN025 which has its own distinct design, but also impressive specifications and performance to back it up.
Seiko Tuna Marine Master SBBN025 Review
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A lot of people appreciate a dive watch but have gotten tired of the classic divers which all look the same. Furthermore, they want a watch that is backed up by performance. And that is exactly what the SBBN025 offers.
It has a completely different design from what you may associate with a diver, and it is also built to last. This watch is sporty, robust, durable, and unique. With that said, it is easy to understand why it is so immensely popular.
As the name reveals, this watch is a ”Tuna”. This name refers to the case design, which derives from the fact that the case reminds of a tuna can. This case design is unique, distinct, and very sporty.
Furthermore, the watch is also a ”Marine Master”, which, as the name suggests, is an indication that this is a serious dive watch.
In this article, we are reviewing and looking closer at the Seiko Tuna Marine Master SBBN025.
Seiko Tuna Marine Master SBBN025 case
The watch is presented with a distinct and bulky tuna case. Its design can be instantly recognizable, and with a diameter of 52mm and a lug-to-lug measurement of 52mm, it is a big timepiece. With that said, it is definitely a watch for everyone, but rather only for those who enjoy the presence of a bulky timepiece on the wrist.
But at the same time, because of its unique case shape, it doesn’t wear in the same way as a traditional watch. Because the lugs are virtually non-existent, the actual case takes up all of the property, and therefore, the lug-to-lug is the same as the diameter. This also allows the watch to wear much more comfortably than watches with large lugs.
As is a distinct trait of the tuna watches, the case has protective shrouds which surround it and are meant to protect the case and bezel. As a dive watch should, it has a unidirectional rotating bezel with a black aluminum insert with 60-minute markings.
Being a serious dive watch, it offers a whopping 1000-meter water resistance. This means it is suitable for essentially all water activities.
The case is made of titanium and has a black hard coating and a ceramic shroud. It is built with a monocoque case for greater durability and reliability. When Seiko presented the first tuna watch in 1975, it was promoted as ” the “ultimate professional diver’s watch”. Since this is a monocoque case, the movement is encased from the front. This removes the need for a screw-down case back and thus allows for better water resistance.
To ensure its water resistance, the case also has a screw-down crown. This is positioned at 4 o’clock in order to make it sit more comfortably on the wrist so that it doesn’t dig into the wrist.
The case and the shroud are both blacked out which adds to the sporty look and nature of this timepiece. Sitting on top of the case, we have a sapphire crystal with an anti-fogging coating.
Seiko SBBN025 dial
Those who are familiar with the original Seiko Tuna will recognize that the dial design of the SBBN025 as it is very similar to the original.
It features a black dial with exceptional legibility. Around the outer edge of the dial, it has white painted minute markers. The hour markers are painted onto the dial with a generous amount of Lumibrite. The minutes hand is painted white and is sword-shaped and has Lumibrite applied to them. The hour hand is short, has an arrow tip, and is also painted white with Lumibrite applied to them. The fact that the hands are painted white helps create a great contrast against the white background.
The Lumibrite used for this watch has a slightly cream color that works as a nod to the original vintage Tuna. The bottom line is that the Lumibrite will glow long and bright.
Seiko Tuna Marine Master SBBN025 movement
The Seiko Tuna Marine Master SBBN025 is powered by the Seiko in-house high-tech quartz movement 7C46. This is a quartz movement with 7 jewels that has hi-torque tolerances and high efficiency. The movement is extremely accurate.
Watch enthusiasts may be scared away by the thought of a quartz watch, but it does have great performance and of course, much better accuracy than regular dive watches.
Furthermore, the quartz movement in this watch is sturdy, and durable, and will handle shocks and bangs without any issues.
Seiko SBBN025 strap
The watch is fitted on an ultra-soft black rubber strap. Rubber straps go very well with dive watches in terms of design. They look sporty, but most importantly, they have great water-resistant properties. The strap is comfortable on the wrist and can of course also be worn on top of a wetsuit.
Specifications
- Lug width: 22mm
- Crown: Screw-down, signed
- Crystal: Sapphire with anti-fogging treatment
- Water resistance: 1000m. ISO Certified
- Diameter: 52mm
- Lug-to-lug: 52mm
- Strap: rubber
- Movement: In-house Seiko caliber 7C46 ( Hi-Tech quartz)
- Accuracy: +/- 15 seconds per month.
- Jewels: 7
- Case material: titanium, super-hard coating
Conclusion
All in all, the Seiko Tuna Marine Master SBBN025 is a serious dive watch that means business. It doesn’t only look like a sporty and robust watch, but it also has the specifications and performance to back it up.
With its shroud design that keeps the case protected and its water resistance of 1000m, it is built to last and will be able to handle any water activity that you subject it to.
With its large size, it’s definitely not for everyone, however, it is perfect for those who enjoy watches that have a bit of presence on the wrist.
With its impressive specifications and durability in mind, it’s safe to say that the Seiko Tuna Marine Master SBBN025 offers exceptional value for the money.
The Seiko Tuna Marine Master SBBN025 is available to order on Amazon.
