- Grand Seiko has announced the arrival of two new dive watches in the blue SLGB023 and the green SLGB025.
- Crafted from High-Intensity Titanium and measuring 40.8mm in diameter, they have 300m of water resistance, a micro-adjust bracelet, and are powered by the calibre 9RB1 UFA.
- Both the blue SLGB023 and the green SLGB025 are available from Grand Seiko boutiques in June, with a local RRP of $17,700.
If you love Grand Seiko watches as much as the Boss Hunting office does, the Japanese watchmaker’s newest diving watches are very, very exciting. Not only do they deliver a smaller case and 300m of water resistance (up from the 200m of previous models), but they also arrived with a massively improved bracelet and an all-new movement that brings the brand’s recently revived U.F.A technology to a proper sports watch.
Kicking things off with a look at the High-Intensity Titanium case, Grand Seiko has significantly refined what’s on offer, making it a genuinely wearable 40.8mm in diameter and 12.9mm in thickness (3mm smaller in diameter and nearly 1mm thinner than existing comparisons). Especially when combined with the High-Intensity Titanium used for both the case and bracelet, we’ve got a pretty lightweight, compact diver on our hands.
As for the bracelet, Grand Seiko has clearly been listening to feedback from collectors and has paired these two new divers with a micro-adjust mechanism that allows for three positions 2mm apart (for 6mm in total). The micro-adjust is perfect for those warmer days when your wrist wants that little bit extra room to breathe, but there’s also an 18mm diving extension if you ever need to secure it over the sleeve of a wetsuit.
Unsurprisingly for Grand Seiko, the blue and green dials are beautifully textured and feature a tide-inspired “Ushio” pattern that we’ve previously seen from the brand, both of which are framed by glossy ceramic bezels in respective matching colours. You’ll also notice a power reserve indicator on the dial and the words “SPRING DRIVE UFA”, which give away the fascinating movement beneath.
It was in 2025 that Grand Seiko debuted its collection of UFA (Ultra-Fine Accuracy) watches, in a nod to a line-up of Grand Seiko’s most collectible vintage watches: the VFA (Very-Fine Adjusted) watches. In short, UFA watches are the most accurate timepieces in the world that are powered by a mainspring (guaranteed to ±20 seconds per year), and the 72-hour power reserve calibre 9RB1 UFA of 2026 follows last year’s release by moving the power reserve indicator to the dial side.
It’s an excellent duo to join Grand Seiko’s current catalogue, and a new set of references that collectors have been waiting for. With a smaller profile on the wrist, lightweight construction, nicely finished dials, and a movement that represents Grand Seiko at its very best, these could well be the brand’s finest modern dive watches.
Both the blue SLGB023 and the green SLGB025 are available from Grand Seiko boutiques in June, with a local RRP of $17,700.
