Customer care
Size guide.
Picking the right Aquastar starts with understanding how a watch will sit on your wrist. The numbers below explain what each dimension means and where each Aquastar model sits.
Understanding watch dimensions
Case diameter
The horizontal width of the case at its widest point, measured in millimeters. The most quoted dimension, but not the most important for fit. A watch with a 40 mm diameter but very long lugs can sit larger on the wrist than a 42 mm with shorter lugs.
Case thickness
From the case-back to the top of the crystal. Affects how the watch sits under a shirt cuff. Aquastar’s current Benthos Professional measures 13.7 mm thanks to a slim case redesign.
Lug-to-lug
The vertical span from the tip of the upper lug to the tip of the lower lug. This is the most important number for fit. If it is wider than your wrist, the lugs will overhang regardless of the diameter.
Lug width
The gap between the lugs that determines which straps fit. Aquastar models use standard 19 mm, 20 mm, and 22 mm lug widths, all easy to find replacement straps for in any material.
How to measure your wrist
Wrap a flexible tape measure around your wrist where you would wear a watch and record the circumference in millimeters. If you don’t have a tape measure, wrap a strip of paper instead, mark where it meets, then measure the strip with a ruler. A typical adult wrist measures between 150 mm (6 in) and 200 mm (8 in).
Aquastar model dimensions
| Model | Diameter | Thickness | Lug to lug | Lug width |
|---|---|---|---|---|
| Benthos Professional | n/a | 13.7 mm | n/a | 20 mm |
| Benthos Heritage MKII | n/a | n/a | n/a | 20 mm |
| Benthos 500 Chronograph | n/a | n/a | n/a | 22 mm |
| Benthos H1 | n/a | n/a | n/a | 20 mm |
| Deepstar III (manual wind) | n/a | n/a | n/a | n/a |
| Deepstar II | 36.75 mm | 13 mm | 46 mm | 19 mm |
| Airstar Chronograph | 39 mm | 14.8 mm | 49 mm | n/a |
| Model 60 | n/a | n/a | n/a | 19 mm |
Cells marked “n/a” are awaiting confirmed measurements. Please refer to the product page for each specific model.
Which size suits which wrist?
A useful rule of thumb based on lug-to-lug:
- Under 160 mm (≈ 6.3 in): lug-to-lug under 44 mm. The Deepstar II (46 mm) is at the upper limit but wears well thanks to its cushion case.
- 160 to 180 mm (6.3 to 7.1 in): any current Aquastar fits comfortably.
- 180 to 200 mm (7.1 to 7.9 in): the Airstar (49 mm lug-to-lug) and the larger Benthos variants sit best on this range.
- Over 200 mm (7.9 in): the Benthos Professional and Benthos 500 Chronograph are ideal.
Still unsure? Tell us your wrist size via the contact form and we will recommend the right Aquastar for you.
