It's been a long time since I reviewed Seiko dive watches, and without a doubt, I value them highly.
Seiko is one of my favorite manufacturers of sports watches with a rich history of creating quality dive models across various price segments. Seiko's popularity in the world of dive watches is due to their ability to produce both affordable and premium models with thoughtful technical solutions. In recent years, the brand has significantly improved the design of many of its classic models while emphasizing key designs and collections. In the current price range, the Seiko Prospex 1968 Heritage Diver’s GMT SPB519 occupies a middle position between basic mechanical divers and more expensive luxury models with complex mechanisms. I believe there is no need to pay significantly more - Seiko offers many useful features for the price.
Interestingly, Seiko essentially competes with itself by releasing similar models with drastically different price tags. I really like this 42mm GMT diver with a Marinemaster-style steel case, but the existence of similar options priced several thousand dollars higher is confusing. For instance, comparing this SPB519 model with similar Seiko watches priced $2000 more creates confusion. Although the Prospex GMT SPB519 visually resembles the Marinemaster, Seiko does not consider it part of the Marinemaster - these watches are more expensive.
For example, the recently released Seiko Prospex Marinemaster HBF001 has approximately the same size steel case, ceramic bezel, and automatic movement (though with time and date function, not GMT). This three-hand Marinemaster costs $3600, which is $1900 more than the SPB519. Yes, there are slight improvements in the mechanism (8LXX series versus 6RXX), but overall, Seiko creates confusion by offering so many similar models. This is another issue, but most buyers, like me, will browse the Seiko website without deep knowledge to understand the difference.
Can the Seiko Prospex 1968 Heritage Diver’s GMT Be Considered a Marinemaster?
I think it can. For me, a Marinemaster is defined by the case shape, bezel, hand style, and hour markers. The Prospex 1968 Heritage Diver’s GMT has all the characteristic features of a Marinemaster. Personally, I find the Marinemaster aesthetic the most appealing among all Seiko dive models. Over the decades, Seiko has released the Marinemaster in various iterations. To me, this style is associated with the 'Japanese Rolex Submariner,' which I find a very successful concept. Unlike the classic black dial, here we have a light silver dial with red accents and a blue ceramic bezel. Seiko claims this color scheme pays homage to the original 1968 model - a rare way to wear a Marinemaster on the wrist.
Updates and Build Quality of the Seiko Prospex SPB519
If you haven't held a Seiko Prospex in your hands for a while, you'll notice many improvements in the SPB519 model. The ceramic bezel is just one example. The steel case is crafted with high-quality polishing, the bracelet no longer feels like an afterthought, and the clasp is made from solid metal parts rather than stamped elements like before. From a quality and finish perspective, these are truly excellent watches. They are also suitable for diving: Seiko's Lumibrite glows brightly, and the case withstands pressure up to 300 meters. The unidirectional rotating bezel feels sturdy, although its clicks are softer and quieter than those of many more expensive dive models. Personally, I liked the bezel's action and appreciated the engineering thought, but I understand that not everyone will find it appealing.
Case and Ergonomics
The case is made of steel, 42mm in diameter, 13.3mm thick, with a lug-to-lug length of 48.6mm. Despite the thickness, the watch is very comfortable on the wrist. A domed sapphire crystal with anti-reflective coating on the inside is installed above the dial. This design enhances the appearance with a play of light, although for protection, the glass is better made flush with the bezel. The crown without a logo is located at around 4 o'clock - a convenient solution that makes it easy to grasp and eliminates discomfort when wearing.
Hybrid Character of the Watch: Diver with GMT Function
In the article's title, I call this model a hybrid. It's not just a Prospex trying to look like a Marinemaster, but a dive watch with a GMT function. However, it's not a full-fledged travel watch with dual time zones, but rather a classic diver with additional GMT indication. This means that the ideal buyer is someone who primarily wants a dive watch with the ability to track a second time zone. Firstly, it uses the so-called 'caller GMT,' where the GMT hand is adjusted rather than the hour hand, as in travel models. Secondly, the GMT scale is not prominently displayed - you need to view it at an angle to see the 24-hour numbers printed on the inclined ring around the dial. When viewed straight on, the scale is almost invisible. Often, GMT divers place the scale on the bezel, but Seiko retained the classic 60-minute marking. Therefore, I do not consider this watch a full-fledged GMT for diving, but rather a diver with an additional GMT function, which many use as an AM/PM indicator - as do I.
Seiko 6R54 Movement: Reliability and Functionality
Inside is the Seiko 6R54 automatic caliber with a frequency of 3 Hz and an impressive power reserve of about three days. The movement provides time display, date, and adjustable 24-hour hand. The Prospex case protects the movement from magnetic fields at a decent level. Seiko does not claim that the 6R54 is as accurate as the more expensive 8L45 caliber in the Marinemaster, but in my tests, it showed good accuracy and reliability. The case back is not transparent, adorned with laser engraving of a wave and some image, the meaning of which is unclear.
New Bracelet Clasp: Quality and Convenience Improvement
The SPB519 is the first watch where I saw the new steel folding clasp. It is equipped with a locking mechanism and a micro-adjustment system. The mechanism operates smoothly and reliably, a noticeable step forward compared to previous bracelets even on expensive Seiko models. The only downside - when the micro-adjustment is open, it resembles an extension for a diver's bracelet rather than an elegant solution for increasing size. The metal bar extends outward, whereas typically the additional link is hidden inside the clasp. Aesthetically, most users would prefer to keep the micro-adjustment fully closed. This issue does not affect the more expensive Prospex Marinemaster models, where the bracelet and clasp are arranged differently. According to Seiko, the SPB519 is the first non-limited watch with such a clasp.
Conclusion: Position in the Line and Recommendations
Seiko continues to produce some of the best dive watches, although the range and similarity of models can make understanding differences difficult. The Seiko Prospex 1968 Heritage Diver’s GMT is a multi-functional model that mostly succeeds in its task, despite some features and shortcomings. The brand tries to maintain recognizable aesthetic pillars while differentiating price levels, which is challenging and creates confusion for buyers. Therefore, I strongly recommend personally comparing similar models at official dealers.
The SPB519 is not part of a large family, but Seiko offers similar models with different dial colors. Older versions with black (SPB383) and green (SPB381) dials are also available. The new generation features greater water resistance (300m versus 200m) and a new clasp. Besides SPB519, the new generation includes limited SPB509 (blue dial and yellow GMT hand) and SPB534 (black dial with gold accents). Due to limited release, they are $50 more expensive. Personally, I like the brighter silver dial with a blue bezel and red details - this option is unique in the Seiko collection and occupies an optimal price segment between budget and premium Prospex divers.
The retail price for the Seiko Prospex 1968 Heritage Diver’s GMT SPB519 is $1700 USD.
