Classic Fusion straps are not sold by case diameter but by size 1 to 6, and the same case size can need different straps. That is why you need to measure your current strap before you order. Each size is defined by three measurements: A, the full width at the case, B, the narrow tongue that slides into the case (the attachment width), and C, the width at the buckle. Measure all three, compare the shape of the strap end, and match the numbers in the tables below.
Size table: black strap
| Size | A (width at case) | B (tongue) | C (at buckle) |
|---|---|---|---|
| 1 | 25 mm | 19 mm | 22 mm |
| 2 | 21 mm | 14 mm | 18 mm |
| 3 | 23 mm | 15 mm | 20 mm |
| 4 | 25 mm | 17 mm | 22 mm |
| 5 | 23 mm | 16 mm | 18 mm |
| 6 | 19 mm | 13 mm | 18 mm |
Size table: white, blue and brown straps
| Size | A (width at case) | B (tongue) | C (at buckle) |
|---|---|---|---|
| 1 | 27.5 mm | 19 mm | 24 mm |
| 2 | 25 mm | 19 mm | 22 mm |
| 3 | 23 mm | 15.5 mm | 20 mm |
| 4 | 22 mm | 16 mm | 18 mm |
| 5 | 19 mm | 16 mm | 18 mm |
| 6 | 19 mm | 13 mm | 18 mm |
Note that the two tables are different. A size 1 in black is 25 mm at A, a size 1 in white, blue or brown is 27.5 mm. Order by the numbers, not just by the size label.
How to measure before you order
- Take off the strap, or measure it on the watch with a ruler or calliper in millimetres.
- A: the full width of the strap where it meets the case, edge to edge.
- B: the width of the narrow tongue at the very end that fits into the case. This is the attachment width, and it must match exactly.
- C: the width at the buckle end.
- Shape: compare the end of your strap with the photos on the product page: the tongue and the curve where the strap meets the case should look the same.
All three numbers and the end shape must match. We do not give a size by case diameter or reference, because it is not reliable for this watch. If you are between sizes, send us your measurements and a photo of the strap end before ordering.
Classic Fusion vs Big Bang
The two families look related, but the straps are not interchangeable. The Big Bang is sold by case size (44 mm, 42 mm, Unico), the Classic Fusion by sizes 1 to 6. If you own both, see our Hublot Big Bang strap guide for the Big Bang side.
Which colour
- Black is the classic look on titanium, ceramic and gold. Black rubber strap.
- Blue picks up a blue dial. Blue rubber strap.
- Brown warms up a gold case. Brown rubber strap.
- White is the summer strap and suits white dials. White rubber strap.
How to change the strap
Lay the watch face down on a soft cloth. The tongue at the end of the strap (B) sits in the case and is held by the case fixing, so work carefully and with the right tool: our Hublot strap tool is made for this, and it is in the same collection. Fit the new strap, check it is secure, then move your buckle across. Clean the rubber with water and mild soap; see how to clean a rubber strap.
FAQ
Which size do I need for my Classic Fusion?
You need to measure: case size alone does not tell you the strap size. Measure A (full width at the case), B (the tongue that goes into the case) and C (width at the buckle), check that the end shape matches the product photos, and pick the size whose three numbers match. If in doubt, send us your measurements and a photo before ordering.
Are the sizes the same for every colour?
No. Black has its own size chart, and white, blue and brown share another. Size 1 black is not the same as size 1 white, so always read the numbers on the product you order.
Will a Big Bang strap fit my Classic Fusion?
No. The Classic Fusion has its own collection. The Big Bang straps are cut for the Big Bang case.
What warranty do the straps have?
All our Classic Fusion straps are rubber, with a lifetime warranty on the rubber.
More on the brand in our Hublot strap guide, or browse all Hublot straps. Helvetus is not affiliated with Hublot.
