Seiko’s 62MAS Reissue Gets New Enthusiast Friendly Variants, and the Tuna Gets an Upgrade

The old expression “When it rains, it pours” often refers to the sudden piling on of bad news. But now, in this very strange spring of 2020, I hereby move to reclaim this often heard phrase as a sign of abundance of things that are good. Exhibit A: the flood of recent release news from Seiko, a brand that we’re seeing more than ever is really listening to their customer base, and seemingly giving them everything they ever wanted, whether they realized it or not. We’ve covered a number of recent Seiko releases that seem aimed squarely at the forum dwelling and Instagram ready enthusiast, including the recent relaunch of the famed Capt. Willard and a trio of divers meant to evoke the Japanese watchmaker’s most classic forms. Today we’re looking at two sets of releases that go back to the well in the best way possible, making classic vintage inspired designs available to the masses at friendly prices.

Seiko SPB143, SPB145, SPB147

  • Case Material: Stainless steel 
  • Dial: Gray, brown 
  • Dimensions: 40.5mm  
  • Crystal: Sapphire       
  • Water Resistance: 200 meters   
  • Crown: Screw down                  
  • Movement: 6R35
  • Strap/bracelet: Stainless steel, rubber    
  • Price: $1,000 – $1,200
  • Reference Number: SPB143, SPB145, SPB147
  • Expected Release: July

Seiko S23629, S23631

  • Case Material: Stainless steel (S23629), Titanium (S23631)
  • Dial: Black 
  • Dimensions: 47.7mm (S23629), 49.4mm (S23631)  
  • Crystal: Sapphire       
  • Water Resistance: 300 meters (S23629), 1000 meters (S23631)   
  • Crown: Screw down                  
  • Movement: 7C46
  • Strap/bracelet: Rubber    
  • Price: $1,450 (S23629), $2,400 (S23631) 
  • Reference Number: S23629, S23631
  • Expected Release: July 


First up, a release that many saw coming (or maybe they willed it into existence) when we brought you news just last month of the forthcoming SPB149, a watch that finally, at long last, brought the classic aesthetic and proportions of the legendary 62MAS to the masses at an affordable price point. Except, the “masses” in this case tops out at 5,500 enthusiasts. Not the most limited of limited editions, but if you were hoping for a chance to buy a watch in this form factor without the stress of the hunt and frantic calls placed to ADs, Seiko’s got you covered with the SPB143, SPB145, and SPB147.

These non-limited editions of the 62MAS tribute are available in a few different configurations. On the surface, the SPB143 is the most faithful to the original 62MAS with its gray dial and black bezel combination. The SPB145 is very similar, but sports a dial with a brown tone, which is reminiscent of tropical aging. The SPB147 is the flashiest of the bunch, with gilt accents on the dial and bezel. This is also the only variant to come on a rubber strap – the SPB143 and SPB145 each ship with an Oyster style bracelet. Prices start at $1,000 for the SPB147, and move up to $1,200 for the references with bracelets. 

As we pointed out excitedly with the SPB149 announcement, this is a huge moment for Seiko enthusiasts. While the 62MAS form factor has been roughly translated to modern Seikos in the recent past, there was always a compromise. Dial elements were off in the case of the SPB051, for example. And the SLA017, a pretty accurate clone of the original watch, was prohibitively expensive for many fans at around $4,000, and limited to 2,000 pieces worldwide. With this announcement of three new permanent additions to the catalog, plus the earlier and more easily accessible limited edition, fans of the 62MAS are suddenly spoiled for choices.  

Next up is a release that’s a little more niche than the aforementioned SPBs, but no less interesting to fans of the more offbeat side of vintage Seiko. The S23631 and the S23629 are the newest entries in Seiko’s long line of Tuna cased watches, with a distinctive, love it or hate it shroud surrounding the bezel, creating a hockey puck-like case shape. This is the chosen format for many of Seiko’s modern professional divers, made for people who are far more concerned with utility and durability than good looks. Which isn’t to say these watches aren’t good looking – they just require a slightly different perspective. 

While both of these models are suitable for saturation diving, the S23631 is the more robust of the two, with a full 1000 meters of water resistance and a case measuring 49.4mm. The case is in titanium, with a ceramic shroud, and the watch is mounted on a rubber strap. The S23629 is just a touch smaller at 47.7mm in diameter, and is rated to 300 meters of water resistance, which of course is plenty, even for pros. Unlike it’s slightly bigger brother, the S23629 has a case made of stainless steel, but it shares the same rubber strap. 


Both of the new Tunas feature Seiko’s 7C46 movement, a high accuracy quartz caliber from the inventors of the technology. There’s a real pleasure in knowing you have the “best” of something, and that’s what you’re approaching with these quartz movements, which are designed with long term reliability in mind, and are anything but disposable. While not everyone will see an extremely well made and highly accurate quartz movement as a feat of engineering, for those that do, these watches represent something close to the ultimate in accurate, reliable, and durable divers. 

The S23629 will retail for $1,450, and the S23631 will sell for $2,400. Both will hit stores in July, as will the SPB releases at the top of this post. Seiko

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Zach is a native of New Hampshire, and he has been interested in watches since the age of 13, when he walked into Macy’s and bought a gaudy, quartz, two-tone Citizen chronograph with his hard earned Bar Mitzvah money. It was lost in a move years ago, but he continues to hunt for a similar piece on eBay. Zach loves a wide variety of watches, but leans toward classic designs and proportions that have stood the test of time. He is currently obsessed with Grand Seiko.