Christopher Ward
Christopher Ward C63 Sealander 39 Strap Size — 20mm Lug Width
The Christopher Ward C63 Sealander 39 has a 20mm lug width, so it takes a 20mm watch strap.
Lug width20mm
| Lug width | 20 mm |
|---|---|
| Case size | 39 mm |
| Lug-to-lug | 45 mm |
| Thickness | 10.9 mm |
| Spring bar Ø (typical) | Not confirmed |
| End type | Straight |
Which reference do you have?
Similar-looking models can take different straps. Your reference number is on the case back or your papers.
| Model | Case | Strap |
|---|---|---|
| C63 Sealander 36mm | 36mm | 20mm |
| C63 Sealander 39mm | 39mm | 20mm |
| C63 Sealander 42mm | 42mm | 22mm |
Strap styles that fit
- NATO / Zulu20mm fits if the strap's thickness clears the case under the bars.
- PerlonWoven pass-through, 20mm.
- 2-piece leatherStraight ends fit flush.
- Rubber / siliconeDivers & sports fit well.
- Milanese / meshStraight-end 20mm mesh fits.
- Metal braceletNeeds 20mm end-links shaped for this case.
▲ The 36mm and 39mm Sealanders take 20mm; the 42mm takes 22mm.
Fit & sizing notes for the C63 Sealander 39
- Width: buy 20mm straps. Tapered straps listed as 20/18mm or 20/16mm fit too; only the first number has to match. See strap sizes explained.
- Spring bars: 20mm long. We haven't confirmed the diameter for this model, so measure the old bar before buying replacements (spring bar sizes).
- Wrist fit: at 45mm lug-to-lug it should sit within the top of wrists from about 15.0cm up (rule of thumb: lug-to-lug under ~30% of wrist size). That's longer than 16% of the watches in our index. See what size watch suits your wrist.
- Strap thickness: at 10.9mm thick it's mid-thickness, so most straps suit it; padded leather and NATOs both balance well.
Sources & corrections
Lug width checked against: Christopher Ward: straps and bracelets (C63 / Sealander sizes); Christopher Ward: C63 Sealander Automatic 39mm; WatchClicker: C63 Sealander 36mm review. Last checked 26 October 2026.
Spec wrong for your watch? Send us a correction with your reference number.
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Christopher Ward C63 Sealander 39 — strap questions
What size strap does the C63 Sealander 39 take?
The Christopher Ward C63 Sealander 39 has a 20mm lug width, so you need a 20mm watch strap.
Will any 20mm strap fit the C63 Sealander 39?
Most will. Width is the main thing to match, but also check that the strap's spring-bar holes suit the bars, and that the strap is thin enough to clear the case between the lugs. A metal bracelet needs 20mm end-links made for this model.
What spring bar size does the C63 Sealander 39 use?
20mm long. We haven't confirmed the diameter for the C63 Sealander 39, so measure the original bar with calipers before buying replacements.
Is the C63 Sealander 39 good for strap swapping?
Yes. With standard 20mm spring-bar lugs, NATO, leather, rubber and mesh straps can all be fitted with a spring-bar tool.