The Seiko Marinemaster 300m and the Virtue of Not Caring

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The Seiko Marinemaster 300m

No matter the size of your collection, itís always going to have a few stars. A couple of watches that are often seen at special occasions (though not only at special occasions, for many), watches that you want to wear whenever something important is happening in your life. For me, those two watches are my TAG Heuer Monaco Vintage and my Omega Speedmaster Professional. Sure, those are coincidentally the most expensive watches in my collection, but thatís not what makes them special; they were gifts from the two people in my life I hold most dear (the Monaco from my brother and the Speedmaster from my mother). Yes, the Monaco is a limited, individually numbered edition, but even though the Speedmaster is replaceable physically by watches that sit in glass cases all over the country, nothing could ever replace the sentiment behind the piece I actually own; so of course, these watches are worn sparingly.

That brings me to the other important watches in the collection. The bruisers. The squad rotation players. The middle relievers. Unsung heroes that deal with the everyday, donít get taken out to the big parties, and often end up in places they donít want to be. And thereís something really, truly wonderful about them.

The reason behind buying mine is pretty simple and, if Iím honest, a bit shallow. The job could easily be done by a G-Shock, my beloved Suunto, a Timex, any number of Seiko 5 models, other random Casios, quartz Victorinox watches, lower range Hamiltons, and the list goes on and on and on. But I wanted something nice. Something that was replaceable, but didnít feel like it could be replaced at a momentís notice. Something that was durable, stylish, and something with a little WIS cred. And yes, that ended up meaning that it was something that was a bit more expensive than the watches I mentioned. It was also a bit of a gift to myself, something that said Iíd reached a point in my career that I was able to splurge on something that I didnít have to take off to run the grill at a barbecue (a career Iíve since abandoned, incidentally).

The watch I settled on was the Seiko Marinemaster 300m SBDX001. Eventually I also picked up a Breitling B-1, with an eye to replace the Marinemaster 300m, but, in true WIS fashion, I ended up keeping both. So why now sing the praises of the watch that just eight months ago I was looking to replace? (Iíll gush all over the B-1 and anadigis like it in a later post)

Well, itís its virtues that kept me from selling it. Its quality, 8 months after its very high quality replacement arrived, is what keeps it on my wrist day after day. I figured itís time I tried to put them on (digital) paper. What makes the MM300 such a difficult watch to get rid of? Itís kind of like that murderous cat in that childrenís song (if you donít know the song, the cat is basically an unkillable burden to Old Mr. Johnson, who, if you analogize to Hans Gruber makes the cat John McClane, but before all the ridiculous sequels I prefer to pretend donít exist); no matter what I do, no matter what I say Iím going to do, the watch just ends up magically on my wrist. Why?

The MM300 on my Liverpool colors NATO; a matchday staple for me

I mean, itís really just another black dial dive watch in a sea of black dial dive watches. A normal person (as distinguished from the likes of us) wouldnít be able to tell it from a Rolex Submariner, an Orient Mako, its lesser Seiko cousins, or the plethora of microbrand divers that keep popping up on forums and Kickstarter.

Seriously, the MM300 is a bit boring, isn't it? They say perfection is boring, so it makes sense. I've had mine for a little while now, and while I often think about trying to find something to trade it for, my MM300 just keeps finding its way on to my wrist. It's not like it's my favorite watch in my collection. It lags behind my Speedmaster and Monaco, for sure. It might even be edged by my B-1.

But there's just something about it. It's gorgeous. Proportionally perfect. The bracelet, though not my favorite design, is really comfortable and the clever clasp finds me ratcheting it closed just for fun. And just about the perfect size. And it's a weird size, too. No one knows what to call it. It's got a 42mm bezel, but it's certainly not 42mm, since it has a 44mm case. But it's definitely not 44mm, since you mainly see the 42mm bezel. But it's definitely not 42mm..... (I call it "about 43mm"). And its simple, but stunning, aesthetic means that itís versatile; it looks good on any number of straps, from no-nonsense NATOs to slightly inappropriate leathers.

IWL member birdynamnam uses his superior photo skills to show the MM300's versatility and beauty on brown leather (photo used with permission)

It's true that I got the MM300 out of curiosity. I'd had Seiko divers in the past, and few lasted very long. SRP043K2 was sacrificed to see what everyone was talking about with the Sumo. Orange Sumo was sacrificed for the more conventional blue Sumo. Blue Sumo got the ax too, for having a bracelet I didn't really like couple with lugs holes that extended too far from the case. I was going to get myself a Seiko ďShogunĒ SBDC007. It was the right size, itís a great looking watch, and the price was absolutely right. I even like the quirky Monster hands its got. But part of me felt that would have just been another rung on the Seiko ladder up to the MM300, so I decided to just take the plunge. I scoured the listings for one that had depreciated to a level that I found more palatable than the (very reasonable) list price, and finally came across one that wasnít much of a discount, but came with a replacement bezel (which I still havenít installed), a sapphire crystal, and a triple gasket crown. Iím still not sure whether I, a man who doesnít dive, swim, or go into the ocean, will get much use out of the triple gasket crown, but I am very happy with the sapphire crystal. And having a backup bezel means I no longer fear doorways. If it hits, it hits. I just donít care. Iíve got a replacement sitting in a box. No worries. And really, isnít that all you can ask for when it comes to a larger watch? To be able to wear it without fear?

More versatility from the MM300...again on book or notebook, since I live in casebooks and case briefs now

Iím not the kind of guy who has a loupe. I donít inspect watches at a microscopic level, either. But I do think I have an eye for quality. And the MM300 feels quality. It has a heft that implies quality, but itís not so heavy that it feels like Seiko was trying to imply quality by adding heft. The bracelet is comfortable, even if I donít love the design aesthetically. It fits pretty well to the case (though I hear it doesnít always fit as flush as mine does). The bezel is assuredly firm in its turning, it feels good to turn, if difficult at times, even though that might just be mine. Itís timed many a chicken in the oven (and thatís not a euphemism) with aplomb. Oh, and the lume. The lume is strong, picks up ďchargeĒ easily, and lasts quite a long time, as my many sleepless nights can attest to.

I've spent many hours watching night turn to day by the impeccable glow of this lume

Iím not much of a movement guy, either. If it keeps reasonable time, is reliable, and doesnít make me think too hard about it, Iím happy. Iím not one for decorated movements, either. And the MM300ís movement does just that. Itís not the most accurate timekeeper Iíve ever owned, but the last time I timed it, when I was inclined to do such things, it was running around +5 seconds per day, which is pretty good Iíd think (so say the Swiss, anyway). Nowadays, I measure accuracy by ďdays to readjusting the timeĒ. Itís unscientific, but the intervals are long enough that I can easily forget when the last time I had to set it was.

And thatís why watches like the MM300 exist for those of us who donít actually dive. And itís not just for making people think Iím not afraid of sharks (I know the stats say itís a long shot, but with my luck, I will absolutely be eaten by a shark; Iíll be the guy people talk about when they say ďwell, thereís only one fatal attack a year on averageĒ, and really, Iíll be fatally attacked once my improbable plane crashes into the ocean--pilot watches are another issue). And itís even more than wearing a watch thatís offers the promise of the unexplored deep on your wrist. The sea is a vast and seemingly unending mystery, one that offers wonders and the occasional drink out of a coconut on the beach. Yes, thatís one of the reasons that fuels my love of dive watches, beyond just their practical advantages to dress watches; I get to look at my watch and go to my happy place in times of need. Itís a quiet beach, practically abandoned, warm, but not so hot you canít wear a long sleeve shirt (I hate short sleeves, the summer can go to hell); Iím sitting there, feet up, drink in hand, in the shade, sunglasses on while Iím reading a book (an actual book, not my Kindle). Waves are lapping the beach and no one is bothering me. And the sea and the salt air and the occasional spill donít trouble my trusty MM300 one bit. It's a strange fantasy, since I don't much like the beach, either. Sand gets everywhere. Perhaps that's why it's a fantasy, perhaps that's why any fantasy is a fantasy.....sorry, I was daydreaming a bit there.

IWL member MarkO took this wonderful picture of his MM300 at his beach paradise (Photo used with permission)

Okay, back on track. The MM300--and durable squad players like it--really does have a special place in my heart and a worthy spot in any collection. I donít have to worry about it. I can wear it, admire its beauty, enjoy its function, or just wear it and not worry one bit about what 30m of water resistance really means (can I wash my hands, but have to dry them carefully?) or whether or not that crystal scratch is going to polish out or whether Iím sweating too much for the leather. And what a lovable quality a freedom from worry is.

(Special thanks to birdynamnam and MarkO for letting me use their photos for this piece)

Updated Sep 2, 2015 at 02:40 PM by Raza



  1. Dan R's Avatar
    Given that most of my diving is at a desk, I have always been intrigued with the Seiko models. So I did get one, but perhaps not as adventurous as yours. By that, I mean it is rated for only 200M, but it does have the crown at the 3 o'clock position and it has a white dial with an almost hob-nail texture. Date only. Automatic of course. The hands are a little more classical in look. Big stainless head with matching bracelet.

    I went through 10 pages of ebay listings, but did not see it in there. It had a peculiar name as I recall.

    But I do like it and wear it often in a rotation.


  2. Raza's Avatar
    Quote Originally Posted by Dan R
    Given that most of my diving is at a desk, I have always been intrigued with the Seiko models. So I did get one, but perhaps not as adventurous as yours. By that, I mean it is rated for only 200M, but it does have the crown at the 3 o'clock position and it has a white dial with an almost hob-nail texture. Date only. Automatic of course. The hands are a little more classical in look. Big stainless head with matching bracelet.

    I went through 10 pages of ebay listings, but did not see it in there. It had a peculiar name as I recall.

    But I do like it and wear it often in a rotation.



    Do you have a picture of your Seiko? I'm sure someone on the forum will be able to identify it. I'm hardly an expert myself, but I would bet someone here knows what you have.
  3. Dan R's Avatar
    Someone chimed in. It's a Samurai!Dan
  4. iyonk's Avatar
    My Grail Seiko diver... thanks a lot for the excellent writing Raza..

    i'm a fan of variety, but if i could start over again or if i can trade my collection or IF i can only have one seiko... this MM300 would be IT!

    hope you could keep that watch and it will be a great companion for good ..
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