Seiko Marinemaster SJE101 Review: Divisive But Wears Like A Dream

The Seiko Prospex Marinemaster SJE101 1965 Diver’s Modern Reinterpretation is definitely a mouthful, but it’s definitely with purpose. Part of the higher-end Seiko Luxe family, the SJE101 evokes two icons — the 62MAS and Marinemaster — but can it live up to those lofty expectations? The answer, as you can imagine, is mixed. What’s for sure, though is that this is a uniquely wearable Seiko Prospex dive watch that measures less than 40mm and has some really impressive finishes. That said, the Marinemaster title carries a lot of expectations with it, and there has been a fair share of discourse about whether it lives up or not.

Seiko Marinemaster Context

What exactly is the big deal with the Seiko Marinemaster? Let’s take a look at how it came to be such a lauded name in the diver category. The first watch in the collection was actually the Seiko Marinemaster Quartz SBCN005, aka the Transocean from 1999. This was a 44mm-wide titanium watch that was highly functional with barometric pressure measurement and barometric trend display. A year later in 2000, the Marinemaster SBDX001 was released, boasting 300 meters of water resistance and no helium escape valve. The Marinemaster family would continue in production until about 2018, when it began to disappear in favor of the larger Prospex family. But about five years later, the Marinemaster would come back in the form of this collection.

More than a couple of people have asked whether this is “really a Marinemaster” due to the lower water resistance and more luxury packaging. Honestly, it’s a pretty fair point to raise, and to be honest I don’t think I’ve really got a strong argument to make against it. What it is, however, is a very wearable and reasonably sized high-end diver that stands out from the crowd while retaining that down-to-earth Seiko identity.

Seiko Marinemaster SJE101 Case and Bracelet

The Seiko Prospex Marinemaster 1965 Diver’s Modern Reinterpretation family debuted in 2023 and was received warmly for its more contemporary, consumer-friendly changes. The most obvious was the new case that shrunk from 44mm down to an ideal 39.5mm wide and 12.3mm thick (albeit with 200 meters of water resistance rather than 300 meters). And you can see the 62MAS design inspiration throughout, with those rectangular indices and hands.

I do have to say that this watch presents a bit of a confusing proposition for the purists as the 200m water resistance and 62MAS design don’t really shout “Marinemaster” which is a fair point. There’s also the crown at 3 o’clock here rather than 4 o’clock and gone is the mono-bloc case construction. But with those justified nitpicks out of the way, how does the SJE101 deliver on its own terms?

First off, the finishing on this case is really impressive and goes a long way in justifying the “Luxe” price tag. There are wonderfully beveled surfaces alongside brushed and polished finishes that create a luster and glimmer that extends from the case through to the bracelet. Speaking of, this is a five-link bracelet that was debuted alongside the SJE101. The two outer links and the center link are done with a brushed finish while the thin links flanking the center have a mirror-polish finish. The result looks fantastic and also wears really nicely on the wrist. All that said, it’s disappointing to not have a micro-adjust clasp at this price point.

The unidirectional rotating bezel has an insert made of ceramic and some really nice knurling for that secure grip. On theme with the rest of the watch, the bezel has a very polished/mirrored finish that bounces and reflects light dynamically.

Seiko Marinemaster SJE101 Dial

Beneath the box-shaped sapphire crystal is a black dial with a nice horizontal stripe pattern. The aforementioned rectangular baton-shaped hands and applied indices are legible and have a healthy amount of lume. The dial really is finished very well with attention to detail in every corner, including alternating brushed and polished finishes which may get lost in photography but dazzle in person. I’m not a stickler about date windows at 4:30, but for some reason this one is just not doing it for me.

A no-date layout would just be so much better here, especially when you consider its footprint due to the relatively smaller case size. That said, the window does match the black dial, which is always a nice touch. I do think having Seiko, Marinemaster, Automatic, and the Prospex logo on the dial is overkill, and just losing one line would make a huge difference here.

Caliber 6L37 Movement

The big reason why Seiko was able to get this Marinemaster in such a compact and thin case size is due to the movement. The 6L37 was initially introduced with the Prospex SJE093 limited edition, which was a previous 62MAS re-edition also released in 2023. Seiko refers to this as a “slimline” 6L movement, made for its divers, with specific attention paid to shock resistance and durability. Indeed this is Seiko’s thinnest mechanical movement ever, measuring 3.69mm thick. As for performance, the 6L37 operates at 4Hz with a fairly middling power reserve of 45 hours and a daily accuracy of +15/-10 seconds.

Another interesting tidbit is that this is the first Seiko dive watch with an exhibition caseback. That said, the movement does look a little small for the case dimensions. And while the movement in nicely finished, I do wish there were more to see here, considering it’s the first time a Seiko diver has a view into the movement. Finally, the blue print on the case back is a little distracting, in my opinion.

Final Thoughts 

For all its divisiveness when it comes to water resistance and Marinemaster branding, Seiko understood that the wearability and finishing is what this watch is all about at the end of the day. The price of $2,800 is just about in line with what you would expect from the Seiko Luxe collection and puts it just in line with pieces like the Longines Legend Diver and the Oris Aquis Date. It’s also priced significantly less than the Tudor Black Bay ($4,975) or a 42mm TAG Heuer Aquaracer ($4,350). You can learn more at seikowatches.com.