· Senior Member
One of the watches I had wanted to check out for quite some time is the Seiko Tuna. A lot has been said about that model and I read quite a bit about it, saw many pictures and made up some ideas.
The stumblimg block has always been the cost, they usually run about two or three times as much as I would like to spend on a watch, and the other factor was that I also have a couple of Marathon JSAR that fill that need for a watch with those features like quartz movement, 300m WR and rock solid. I like the JSAR a lot and I was not about to trade it for a Tuna…
Then some time ago, some "mini tuna" started being produced, the first model has a plastic shroud, this was a step in the right direction but not quite something for me, not yet...
Then a new model came out, the SRP637. This is a new model with a steel shroud and steel case, bracelet and hacking and hand winding movement. I really liked it, although as usual I thought that the Seiko designers did not think the whole thing through. Why? They installed the Seiko Monster bezel and hands on it. While the bezel is not a problem and I actually like it, the hands are all white and in my opinion don't go well with the markers that are chrome framed. Then they also added a black seconds hand... total mismatch from my point of view.
I am sure some people like it that way, but I simply think that there should be continuity with the design and the details. So I said to myself that if I was ever going to get one of these I would have to work out some chrome framed hands to go with the hour markers...
After several projects and the sale of a few of them, I had some funds available and one day I found one of these Seiko SRP637 models for sale and was able to snatch it for a good price.
I have no idea why some people call it mini Tuna, it seems to me that the size is just like the quartz Tuna, 48mm in diameter and it even has longer lugs - 50mm between them. The movement is the hacking and hand winding 4rxx and the dial as the new X logo on it. I don't mind it personally although I would have preferred it less busy, maybe without the X and without the small number in the inner circle, but overall these are small details that fortunately do not affect the overall look in a major way.
I was lucky to have a couple of sets of hands in my stock, first I tried the Sumo hands, did not really like them all that much, mostly because the lume paint is a light green color and was too mismatched with the white of the hour markers. But I liked the shape, so I tried the second option which consisted of a set of hands from another Seiko model people call Sea Urchin. These worked much better and in fact I ended up using the original seconds hand and it seems to me that overall the result is great, definitely an improvement in my opinion.
The case is well finished like most of the Seiko divers, not like a high end watch of course but it is pleasantly satisfactory to the sight and to the touch. It feels solid but it does not weight a ton. Thickness is comparable to a SKX007 or Seiko Monster but the shroud make the watch look larger and fill more real estate on my wrist which is a welcome feature since my wrist is over 8” around.
The bracelet is the familiar one from the Seiko Monster, it is well made and has a diver extension. It is solid and comfortable. The look is of course subjective and while I like it, I can see that it could be upgraded. But not yet, not for me anyway, at this time the watch works well as it is and I am pretty happy with it, I think that these hands work well with the dial and overall design. Short of designing my own, that is…
Here are a few pics showing the watch and the subtle modification.