Two sizes. One measurement. Here's how to get it right first time.
The 10-second answer
Every Marlow strap comes in 20mm or 22mm. That number is your watch's lug width: the gap between the two little arms (lugs) that hold the strap. As a rough rule, watches around 38–40mm across usually take 20mm, and watches around 42–45mm usually take 22mm. Always confirm with one of the methods below before ordering.
What is lug width?
Look at your watch from the front. The strap slots in between two lugs at the top and two at the bottom. The inside distance between those lugs, in millimetres, is the lug width. It's not the size of the watch face, and it's not the size of your wrist.
Three ways to find yours
1. Look it up (easiest)
Search your watch model followed by "lug width", for example "Seiko SKX007 lug width". It's also usually listed in the manual or on the manufacturer's spec sheet.
2. Measure your current strap
Take a ruler with millimetre markings and measure the width of your current strap right where it meets the watch case. Measure at the case, not at the buckle, because most straps taper towards the end.
3. The 1p coin check
A UK 1p coin is about 20mm wide. With the strap removed, hold a 1p between the lugs. If it sits almost exactly in the gap, you're on 20mm. If there's a small but visible gap on both sides, you're most likely on 22mm. It's a quick sanity check. A ruler is still best.
Popular watches at a glance
| Watch | Lug width |
|---|---|
| Omega Speedmaster Moonwatch (42mm) | 20mm |
| Tudor Black Bay 58 (39mm) | 20mm |
| Hamilton Khaki Field Mechanical (38mm) | 20mm |
| Seiko Presage Cocktail Time (40.5mm) | 20mm |
| Seiko SKX007 (42mm) | 22mm |
| Seiko 5 Sports (42.5mm) | 22mm |
| Seiko Prospex "Turtle" (45mm) | 22mm |
| Casio Duro MDV106 (44mm) | 22mm |
Brands sometimes change specs between references, so double-check your exact model if you can.
What if my watch is 18mm, 21mm or 24mm?
Our straps are made in 20mm and 22mm only, and a strap should match your lug width exactly. A 20mm strap on a 21mm watch leaves a gap and looks off. If your watch is a different size, our straps aren't the right fit for it. Our Marlow Three watch case fits any watch, though.
Fitting your new strap
Every Marlow strap comes with quick-release spring bars already fitted. Slide the small pin on the back of the bar, lift the old strap out, line the new one up between the lugs and let the pin click into place. Give it a gentle tug to check it's secure. No tools, no jeweller, about thirty seconds.
Ordered the wrong size?
It happens. You have 14 days from delivery to send it back for a return or swap, as long as it's unworn and in its original packaging. Details are in our returns policy.
Still not sure?
Email marlowsupplysupport@gmail.com with your watch's brand and model (a photo helps) and we'll tell you exactly which size to order, usually within a day.