The Oysterflex
sizing guide.
The right fit is more than a wrist measurement. Match the model, balance the two bracelet sections, and leave room for your wrist to change throughout the day.
Longer section at 12. Shorter section at 6.
A clasp that sits comfortably underneath.
For newer-generation, factory Oysterflex configurations of the Daytona and Yacht-Master. Sky-Dweller width reference included.
Find your chart pairing.
Choose your factory Oysterflex model and enter your wrist circumference. The result reads the chart below—it is a starting point for a fitting, not a confirmed replacement-part order.
Start with your model.
Your section letters will appear here after you enter a measurement.
Yacht-Master results use the supplied family chart; its reference-by-reference applicability still needs confirmation. The estimator does not infer part numbers, retrofit compatibility, or a Sky-Dweller pairing. At a shared boundary or an unlisted measurement, it asks for a fit check.
Three checks. A better fit.
Measure the wearing position.
Wrap a flexible measuring tape around the place you normally wear your watch. Keep it flat and comfortably snug. If using paper, mark the overlap and measure it against a ruler.
Record the actual measurement.
Do not add an arbitrary allowance for comfort. Take two or three readings at a normal temperature. Note whether your wrist varies noticeably through the day.
Check the watch, not just the wrist.
Confirm the full reference, the fitted clasp and, if available, the markings on both current sections. Case dimensions, wrist shape and clasp position all influence the final choice.
A centered clasp matters.
When the two sections are different lengths, our normal fitting starting point is the longer section at 12 o’clock and the shorter section at 6 o’clock. This helps bring the clasp toward the center of the underside of the wrist rather than pulling it around one edge.
That principle is about wrist proportions, not whether the wearer is a man or a woman. The final test is how the clasp sits and how the watch feels on the individual wrist. Some chart pairings use equal sections.
Section orientation is referenced to the dial, not to which hand you wear the watch on.
Leave room in both directions.
Use the section lengths to establish the basic fit, then use Glidelock for fine adjustment. Where the fit allows, start around the middle of its usable travel rather than at either extreme.
- At your normal wrist size: the watch should feel secure, without uncomfortable pressure, and the clasp should sit naturally.
- When your wrist expands: retain room to lengthen the bracelet.
- When your wrist becomes smaller: retain room to shorten it.
Glidelock changes the bracelet length; it cannot correct an unsuitable section combination. Confirm operation against the user guide for your exact clasp.
Two families. Two size charts.
Read from wrist circumference to the 6 o’clock and 12 o’clock section letters. These are the supplied chart ranges in inches, preserved exactly. Do not transfer a Daytona pairing to a Yacht-Master simply because the wrist measurement is the same.
| Wrist sizeinches | 6 o’clocksection | 12 o’clocksection |
|---|---|---|
| 4.80–5.19 | C | D |
| 5.20–5.50 | C | E |
| 5.51–5.99 | D | E |
| 6.00–6.37 | D | F |
| 6.38–6.80 | E | F |
| 6.81–7.19 | E | G |
| 7.20–7.59 | F | G |
| 7.60–7.99 | F | H |
| 8.00–8.43 | G | H |
| 8.44–8.82 | H | H |
The Yacht-Master chart contains rounded range breaks. Measurements falling between the displayed ranges need confirmation. The supplied chart does not identify separate 37, 40 and 42 mm fit tables.
| Wrist sizeinches | 6 o’clocksection | 12 o’clocksection |
|---|---|---|
| 5.04–5.43 | C | D |
| 5.43–5.91 | C | E |
| 5.91–6.26 | D | E |
| 6.26–6.69 | D | F |
| 6.69–7.09 | E | F |
| 7.09–7.52 | E | G |
| 7.52–7.91 | F | G |
| 7.95–8.39 | F | H |
| 8.39–8.86 | G | H |
| 8.86–9.25 | H | H |
Shared endpoints appear in adjacent Daytona rows. The supplied chart also leaves 7.91–7.95 in without a continuous range. The estimator will not invent a pairing for an overlap or gap.
Letters describe section lengths within the relevant bracelet system. A letter alone is not a complete Rolex part number or proof that a section fits another model. Confirm the full section reference, case attachment and clasp compatibility before ordering.
Know the lug width.
Lug width is the opening between the case lugs where the bracelet attaches. It is not the watch’s case diameter, the section length or the width of the clasp. Matching that one dimension does not establish interchangeability.
Yacht-Master 37
18 mm268655
Calibre 2236
Factory Oysterflex
Yacht-Master 40
20 mm126655
Calibre 3235
Factory Oysterflex
Yacht-Master 42
21 mm226658 / 226659
Calibre 3235
Factory Oysterflex
Gold Daytona
20 mm126515LN / 126518LN / 126519LN
Calibre 4131
Factory Oysterflex
Sky-Dweller
21 mmFactory Oysterflex models only.
Width reference—not a size-pair chart.
Widths above follow the supplied width reference. Have the exact watch and section part codes checked before a purchase. This guide does not cover metal-bracelet conversions, aftermarket straps or earlier-generation fitments.
Flexible outside.
Engineered within.
Rolex describes Oysterflex as a bracelet. Inside each section is a flexible metal blade made from a titanium-and-nickel alloy, overmoulded with high-performance elastomer. Cushions on the underside help support the bracelet against the wrist.
The result combines a flexible feel with an internal metal structure. It conforms as it is worn; that is not an instruction to bend, heat or permanently reshape the core. It should not be treated like a cut-to-length rubber strap.
What the clasp does—and doesn’t do.
The current Oysterflex Daytona uses an Oysterlock safety clasp with Rolex Glidelock. On the Yacht-Master Oysterflex system, Rolex describes six notches of approximately 2.5 mm, providing about 15 mm of adjustment.
That travel is for refining an already appropriate fit. If the bracelet only feels right with the adjustment fully open or fully closed, or the clasp sits off-center, have the section pairing assessed.
The practical questions.
Is the calculator a guaranteed fit?
No. It matches a measurement to the supplied family chart, without checking the physical watch. Wrist shape, case fit, fitted clasp and the exact section part numbers still need verification. A fitting with us or an Official Rolex Jeweler is the final step.
Why can the same wrist need a different pairing?
The watch case and clasp form part of the total circumference. Their dimensions and the way they sit on your wrist affect the length needed from each section. Two people with the same wrist circumference can also have different wrist shapes.
What if I am between sizes or exactly on a boundary?
Do not automatically round up or down. Recheck the measurement, note your current section letters and clasp position, and ask for a fit assessment. Some displayed ranges overlap at an endpoint, while others leave a small gap. The estimator makes those limits visible rather than concealing them.
Can I use the same letter from a different Rolex model?
Do not assume so. The size letter is only one part of the specification. The full section reference and compatibility with the watch’s attachment and clasp must match. The same lug width is not sufficient to confirm a replacement.
Can Oysterflex be cut or stretched to fit?
This guide does not recommend cutting, stretching, heating or bending an Oysterflex section. Choose the correct factory section and use the clasp’s intended adjustment. Have replacement work performed by someone qualified to confirm the parts and their secure attachment.
Why is there no Sky-Dweller pairing result?
A Sky-Dweller-specific sizing chart has not been supplied for this guide. Its width is included for context, but a Daytona or Yacht-Master table should not be used as a substitute.