A. Lange & Söhne · 1815

Strap for 1815 Rattrapante Perpetual Calendar Platinum / Salmon

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

Lug width20 mm
Case diameter42 mm
Reference421.056FE
Family1815
MovementA. Lange & Söhne caliber L101.1 hours, minutes, small seconds | date, day, leap year, month, perpetual calendar | Chronograph, column wheel, Rattrapante | moonphase | power reserve indicator
Year2023
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 1815 421.056FE

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The 1815 421.056FE, seen from the bench

The A. Lange & Söhne 1815 421.056FE in platinum represents German watchmaking purism with the Glashütte Manufacture heritage dating to 1845. This model features a 41.90 mm platinum case paired with a 20 mm lug width, housing the in-house caliber L101.1 movement. The L101.1 delivers a perpetual calendar, flyback chronograph, 72-hour power reserve, and 4 Hz frequency with 54 jewels and visible movement through a sapphire caseback.

Frequently asked questions

What is the lug width of the A. Lange & Söhne 1815 421.056FE?

The lug width of the A. Lange & Söhne 1815 421.056FE is precisely 20 mm. This dimension represents the exact space between the two lugs of the case, where the strap must fit without play or lateral tension. It is a precise and non-interchangeable measurement, typical of Glashütte Manufacture's classical models. To verify it, use a digital calliper positioned perpendicularly between the metal lug pins.

What is the best strap for the A. Lange & Söhne 1815 421.056FE?

For the platinum 421.056FE, the finest strap option is alligator leather in medium brown or black tone. Alligator offers naturally regular grain and develops a silvered patina at wear points, creating perfect aesthetic dialogue with platinum. A sophisticated alternative is shell cordovan, which acquires natural lustre with ageing. Both materials embody the aesthetic dignity that platinum demands.

How do I change the strap on my A. Lange & Söhne 1815?

To change the strap, you will need a spring bar tool. Position the flat end of the tool in the small hole beneath the lug, applying gentle inward pressure to compress the spring. Once released, extract the metal pin and remove the old strap. Insert the new strap through the pin and reinsert the lug into the case. Repeat the operation on the opposite lug. If you are not experienced, we recommend contacting Casati Milano for safe replacement.

Is there an aftermarket strap compatible with the A. Lange & Söhne 1815 421.056FE?

Yes, any strap with a 20 mm lug width is compatible with the 421.056FE. MilanoStraps offers a dedicated collection of straps in alligator, shell cordovan, calf leather and other noble materials, specifically designed for this measurement. We recommend choosing premium materials—such as alligator or vegetable-tanned calf—to maintain the aesthetic dignity of platinum. Casati Milano can create custom straps with personalised consultation.

How long does a leather strap last on a watch?

A noble leather strap—alligator, shell cordovan or quality calf—has an average lifespan of 3-5 years with regular wear (4-5 days per week). Durability depends on frequency of use, climatic conditions and care. A strap exposed to frequent perspiration or intense humidity ages more rapidly. It is advisable to rotate between multiple straps to dilute wear and preserve each piece. Casati Milano provides an 18-month warranty on manufacturing defects, regardless of the strap's natural ageing.

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