Lug Width Marking — What This Mark Means
A number stamped between or on the lugs indicating the distance between them in millimeters. This measurement determines which strap or bracelet width fits your watch.
What This Usually Means
The lug width is the distance between the inner edges of the lugs where the spring bar sits. This measurement, typically in millimeters (18mm, 20mm, 22mm, etc.), determines the correct strap or bracelet width for your watch. An incorrect width won't fit or will leave unsightly gaps.
Where to Find It
When present, it's usually stamped on the inner surface of the lugs, visible when the strap or bracelet is removed. Not all watches have this marking, so you may need to measure manually with calipers.
Advertisement
Common Variations
Standard lug widths include 18mm, 19mm, 20mm, 21mm, 22mm, and 24mm. Some watches have asymmetric lug widths (different at 12 and 6 o'clock) and proprietary strap attachment systems that don't use standard widths.
Common Misconceptions
Lug width is not the same as case diameter or case width. Also, some people assume straps must match exactly, but a 1mm difference can sometimes work in a pinch. Proprietary strap systems from brands like Casio or Apple don't use standard lug widths.
What to Do Next
If you can't find a marking, measure the distance between the lugs with calipers or a ruler. Use this measurement when shopping for replacement straps, NATO bands, or aftermarket bracelets.
Advertisement
Related Markings
A number stamped on the end links of a bracelet identifying their specific shape and size. This number is critical for f
Case Reference NumberA manufacturer-assigned reference number identifying the specific watch case design, dimensions, and material. This is t
Case Size IndicatorA marking indicating the watch case diameter or dimensions, typically in millimeters. This helps identify the watch mode
Commonly Seen On
Related searches
Frequently asked questions
What is lug width?
The distance in millimeters between the inner edges of the watch lugs, determining which strap width fits your watch.
How do I measure lug width without a marking?
Remove the strap and measure between the inner edges of the lugs with calipers or a small ruler. Measure in millimeters.
What's the most common lug width?
20mm and 22mm are the most common. Smaller watches often use 18mm or 19mm, while larger ones may use 24mm.
Can I use a strap that's slightly off-size?
A 1mm difference may work but isn't ideal. Too narrow leaves gaps, too wide won't fit between the lugs.
Is lug width the same as case width?
No. Case width (diameter) is the overall measurement across the watch face. Lug width is specifically the gap between the lugs.
Do all watches use standard lug widths?
Most traditional watches do, but some brands use proprietary attachment systems with non-standard measurements.