A. Lange & Söhne · Lange 1

Strap for Lange 1 Daymatic White Gold / Silver Guilloche / Tokyo Boutique

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter40 mm
Reference320.040
FamilyLange 1
MovementA. Lange & Söhne caliber L021.1 Hours, Minutes, Small Seconds | Big Date, Day
CasePlatinum

Spring bar

Swiss Standard universal spring bars

The right category for this model · 316L steel, all lug widths 13–26 mm

Straps for the Lange 1 320.040

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Lange 1 320.040, seen from the bench

The Lange 1 reference 320.040 redefines contemporary German watchmaking with its asymmetric dial, exposed construction, and geometric precision. Powered by the manual L021.1 calibre with three-arm balance oscillating at 21,600 semi-vibrations, this 39.50mm platinum case embodies A. Lange & Söhne's uncompromising heritage. The 20mm lug width maintains optical proportions between case, wrist, and dial. Platinum's natural grey-white finish resists oxidation and ages without visible patina, accumulating microabrasions as a record of use.

Frequently asked questions

What is the lug width of the A. Lange & Söhne Lange 1 320.040?

The Lange 1 320.040 features a lug width of exactly 20 millimetres. This dimension is the standard for the original watch's spring bar attachments. Any aftermarket strap with a 20mm lug width will be perfectly compatible. To verify, measure the distance between the two attachment pins on the case: if it measures 20mm, the strap will fit without any issues.

What is the best strap material for the Lange 1 320.040 in platinum?

For a Lange 1 320.040 in platinum, alligator leather is the most coherent choice aligned with the model's DNA. A dark brown or cognac alligator amplifies the watch's authority and creates perfect visual balance. Alternatively, vegetable-tanned calf leather offers a patina that ages gracefully over time, creating a fascinating dynamic between the static metal and the evolving peel.

How do I change the strap on the Lange 1 320.040?

Strap replacement is performed using the spring bars or straight pins that connect the strap to the case lugs. Using a dedicated spring bar tool or the thin tip of a blade, press the pin laterally to release it, remove the old strap, and insert a new one in the same position. This is a straightforward operation requiring no specialised tools, but must be executed carefully to avoid scratching the platinum case.

Is an aftermarket strap compatible with the Lange 1 320.040?

Yes, any strap with a 20mm lug width is fully compatible with the Lange 1 320.040. Aftermarket straps produced by artisanal manufacturers such as Casati Milano often offer superior build quality and material selection compared to factory straps. Compatibility is guaranteed by the standardisation of lug width: 20 millimetres is an internationally recognised standard.

What is the average lifespan of a leather strap for the Lange 1 320.040?

A quality leather strap (alligator or calf) for the Lange 1 320.040 has an average lifespan of 5–8 years if worn daily, extending to 10–12 years with occasional use. Longevity depends on factors such as humidity, sun exposure, frequency of wear, and maintenance. A vegetable-tanned strap typically lasts longer and develops a fascinating patina. The 18-month warranty covers manufacturing defects but not natural wear.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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Casati Milano · Via XX Settembre 15, Milan · by appointment only