21 mm watch strap loops

21 mm is a rare strap width, found on some classic and vintage watches, and finding a loop to match it can be a challenge. Using a 20 or 22 mm loop instead leaves it either too tight or loose, so a true 21 mm loop gives a much neater result.

Because the difference is only a millimetre, measure carefully: measure the width of your strap in millimetres with a ruler at the point where the loop sits, and check the gap between the lugs of the case as well. If both give 21 mm, this is your size.

In 21 mm, loops are offered in faux leather, made from synthetic PU leather. They have the look of a traditional leather keeper, stay supple with daily wear and suit leather and leather-look straps on classic watches. Four shades are available to match the most common strap colours: black, white, brown and coffee brown.

Fitting is quick and requires no tools: unfasten the buckle, slide the loop along the strap and position it just after the buckle. To keep it looking good, wipe it with a soft, slightly damp cloth and let it dry naturally, away from direct heat.