The Seiko Prospex SRPH43K1 Save the Ocean Asia Limited Edition

Seiko Prospex SRPH43K1

Image: Seiko

The Seiko Prospex SRPH43K1 Save the Ocean Asia Limited Edition, which debuted late last year, is the latest in a long line of dive watches attempting to give back to the old big blue. Seiko has been saving the ocean drive on its own for a few years, and this latest model made waves when it was released, no pun intended. The coral protection education program of EEC Thailand (Environmental Education Center Thailand), an environmental and social business organization in Thailand, is one of Seiko’s most recent on-the-ground efforts in this region.

seiko, Environmental Education Center Thailand

Image: Seiko

In the case of the SRPH43K1 Save the Ocean Asia Limited Edition, any dive watch from a brand with the right history — or even a brand with no history at all — is bound to be extremely popular; that is shorthand for completely unattainable, and Prospex has a few variants, with the SRPH43K1 being limited to an unspecified quantity. On that note, this version is made of stainless steel rather than Seiko’s proprietary Ever-Brilliant steel; that version is also limited but differs in a few ways, the most notable of which is the price. The gold-colored knurled crown isn’t something to be concerned about; it’s a feature of the Prospex model in question.

You’ll recall that Seiko has a long history of producing dive watches, as well as tool watches. The Prospex collection, which dates back to 1965, includes a wide range of well-known models. The King Samurai is represented by the Seiko Prospex SRPH43K1 Save the Ocean Asia Limited Edition, which we will refer to as the SRPH43K1 Asia Limited Edition for the rest of this story.

Fans of Seiko will be familiar with what to expect from this large 43.8mm timepiece, but we’ll go over the key specifications now. For the time being, we’ll note that the reason we’re promoting this model is because of its silicone strap. This is the most practical of the many materials that could be used for dive watches for everyday use. The SRPH43K1 Asia Limited Edition is a watch that you could easily wear every day.

Given that water resistance is the first and best feature in daily beaters, the 200m rating is unbeatable. Silicone complements the case’s extreme toughness, allowing the 12.8mm thick case to rest comfortably on the wrist — and, more importantly, in direct contact with the skin. Silicone, not to be confused with silicon, is a wonder material that is perfectly suited for constant contact with human skin — it is, in our opinion, second to none when it comes to weathering sweat and humidity. The band is available in Seiko’s signature accordion style, which allows it to self-adjust to some extent; you could, for example, wear it over a wetsuit. After all, the word “Diver’s” is printed on the dial.

On that note, the dial is a textured blue delight with a stamped design that matches the strap (at least in pictures; we have not experienced the watch in person). The grid pattern on the dial is also a feature shared by many King Samurai variants, so this is a different beast than the other Save the Ocean variants. The unidirectional ceramic bezel, with orange markers that match the sweep second hand, is a unique feature. Lumibrite, which is arguably superior to traditional SuperLuminova, is used to coat the hands and indices on the dial. Finally, Oceania is included in the Asia part of the SRPH43K1 Asia Limited Edition name.

Movement Automatic calibre 4R35 with date; 41-hour power reserve, approximately

Case 43.8mm in steel; water-resistant to 200m

Strap Silicone

Price US$630, approximately