Open-Ended Strap for a WW1 Birch & Gaydon Trench Watch

Open-ended straps exist for one reason: watches whose spring bars are fixed into the case, where a standard strap cannot be threaded on at all. A Birch and Gaydon “Land and Water” trench watch from the First World War is exactly that problem. This order solved it with a custom open-ended strap in black Epsom, cut to 75/115 mm and finished at a 10 mm buckle.

Strap specifications

Strap type	Custom open-ended
Leather	Black Epsom
Length	75/115 mm (3.0 in / 4.5 in)
Buckle width	10 mm (0.39 in)
Buckle	Classic, stainless steel
Watch	Birch and Gaydon “Land and Water” WW1 trench watch

Why these choices

The open end is the whole build. Instead of a tab pierced for a removable spring bar, each end is left as a loop that passes around the bar already in the case and closes back on itself. Nothing has to come off the watch, which matters on a case more than a century old where the bars are part of the case and are not coming out without damage.

Epsom is a stamped-grain calfskin, the leather Hermès uses for bags. It is light and scratch-resistant, and the grain is printed rather than raised, so the leather stays thin and flat where it wraps the bar. Bulk is the enemy in that loop: a padded or heavily grained hide fights the bar instead of sitting against it. Black keeps the strap out of the way of a small silvered dial.

The 10 mm buckle is the part most makers cannot do. The custom strap configurator runs from 8 mm to 30 mm, so a 10 mm tang on a small period case is an ordinary order rather than a special request. The 75/115 mm split gives 190 mm of total length, cut to the wrist on the order rather than to a stock size.

Questions about this build

What makes an open-ended strap for a WW1 trench watch different from a standard strap?

A standard strap ends in a pierced tab that sits on a removable spring bar. An open-ended strap ends in an open loop that wraps the bar already in the case. On a trench watch with fixed bars, that is the only way to put leather on the watch without working on the case itself.

Do I need to know my measurements before ordering?

You need the width across the inside of the lugs and the width you want at the buckle, and the two do not have to match. This strap was ordered at a 10 mm buckle. A jeweler can take both measurements in a minute, and the numbers go straight into the order form.

Every strap is cut and stitched to the measurements on the order, so allow 2–3 weeks to delivery. If your watch has bars you cannot remove, start with the custom open-ended strap and send your numbers; if you would rather stay with the same leather in another color, the Epsom range is a good place to look.