Seiko has a long habit of building watches around an anniversary, and this one carries two. 2026 is the sixtieth year of PADI, the Professional Association of Diving Instructors and the largest diver-training organisation in the world, and it is also the tenth year of the partnership between Seiko and PADI. The brand has marked both with a single reference, the Prospex HBB002, a limited run of the watch most collectors know simply as the Turtle.
The shape collectors already know
The Turtle takes its nickname from the cushion case, a rounded square that Seiko first used on divers in the 1970s and revived in 2016. Here it measures 45mm across, 13.2mm thick and 47.7mm from lug to lug, in stainless steel. That is a large watch on paper, but the cushion shape pulls the lugs in close, so it wears smaller than the diameter suggests. Water resistance is the diver-standard 200 metres, with a screw-down crown set at four o'clock in the Turtle tradition.
The dial is the reason to look. Seiko has gone with an electric sunburst blue, the shade PADI uses in its own logo, and laid the PADI roundel below the centre with the brand's red accents picking out the central seconds hand and the Diver's 200m line above six o'clock. The bezel insert is finished to match. It is a busy dial by the standards of a tool watch, but the layout is the same one Seiko has refined across decades, so legibility holds.
The movement is the familiar one
Inside is the Seiko 4R36, the automatic calibre that powers most of the brand's accessibly priced divers. It runs at 21,600 vibrations per hour, holds 41 hours of power reserve, carries 24 jewels and adds a day-and-date display, which is why the window sits at three o'clock rather than the date-only aperture some Turtles use. It is hand-windable and hacks. Nobody buys a 4R36 for chronometer accuracy; it is bought because it is robust, serviceable anywhere and has been proven across millions of watches. For a $750 diver, it is exactly the right movement.
Seiko delivers the watch on a stainless steel bracelet with a three-fold clasp, a push-button release and a diver's extension. In the box is a second strap, a black silicone band printed along its length with the full Professional Association of Diving Instructors name, which is the kind of detail that reads as either a nice touch or a bit much depending on your taste.
What the limit means
Production is capped at 8,000 pieces worldwide, each numbered individually on the caseback. That is a large number as limited editions go, large enough that scarcity is unlikely to be the draw. The appeal here is simpler: a well-known diver in a colourway tied to a genuine anniversary, at a price that keeps it within reach. The watch reaches Seiko boutiques and selected retailers in July 2026.
Seiko's PADI watches have built a steady following over the past decade, in part because they sit at the affordable end of a hobby where most anniversary pieces do not. The HBB002 continues that line rather than departing from it. It is the Turtle, in PADI blue, for the year both the body and the partnership reached a round number.
