Power Wheels Magazine A Notch Above
Today, Friday, the 25th of September 2026, Timepieces is proud to feature a pair of highly-desirable, highly-collectible, and mythical Seiko Scuba Diver’s watches – the 1997 SKX399 and 1998 SKX401, Reference No. 7S26-0020. The myth around these automatic dive watches revolves around the idea that these were released primarily for the Philippine market, thus, they are affectionately known in local collecting circles as the “Pinoy Diver”.
The SKX Scuba Diver’s watch series evolved from the 1988-1996 Seiko 7002-series, which in turn came from the 1982-1988 “Slim Turtle” 6309-7290 series. With a long 22-year production run (1996-2018), the SKX series became very popular with a standard model lineup that included the SKX007, with its classic black dial and black bezel; the SKX009, with its dark blue dial and red-and-blue “Pepsi” bezel; and the SKX011, with its distinctive orange dial.
All the models in the SKX lineup – from the SKX007 to the SKX401 – share the same 7S26-0020 Reference Number. They all feature a 43 mm stainless steel case with a 21-jewel Seiko 7S26 automatic mechanical movement that pulses at 21,600 beats per hour (BPH) and has a 40-hour power reserve. All SKX models are ISO-certified water-resistant to a depth of 200 meters (20 bar), which makes them suitable for professional diving.
What differentiates the SKX399 and SKX401 from the standard SKX models are their unique and distinct dial markers. Unlike the standard round dot indices found on the popular SKX007, SKX009 and SKX011, the hour markers on the SKX399 and SKX401 are unique, sharp, and geometric/rectangular indices that are encased in polished silver borders. The SKX399 came with a black dial and black bezel, while the SKX401 is fitted with a dark blue dial and red-and-blue “Pepsi” bezel.
Because the SKX399 and SKX401 had limited regional distribution compared to its mass-market siblings, these two vintage pieces now command strong interests among avid Seiko enthusiasts and serious vintage watch collectors. While it has become quite difficult to find these limited-edition Seiko dive watches in original condition, we were able to locate and acquire our 1997 SKX399 and 1998 SKX401 from two different sources.
As you can see, our SKX399, which was produced in November 1997, looks quite fresh and seldom-used. On the other hand, our SKX401, which was manufactured in February 1998, sports a faded Pepsi bezel, which shows that it was worn quite often, possibly during deep dives and ocean adventures. We are proud to be the current custodians of these rare and sought-after limited-edition Seiko Scuba Diver’s watches from the ‘90s.
Model: Seiko SKX399 / SKX401
Reference No.: 7S26-0020
Month/Year of Manufacture: November 1997 / February 1998
Type: Diver’s Watch
Movement: Self-winding/Automatic
Caliber: 7S26
No. of Jewels: 21
Diameter: 43 mm
Thickness: 13.5 mm
Lug-to-lug Length: 45 mm
Lug Width: 22 mm
Weight: 133 grams
