Technical Archive

Swatch
Sistem 51 YIS407G— lug 20mm

Swatch Sistem 51 YIS407G: 20mm strap. Alligator, box calf, shell cordovan and rubber, cut and stitched in Milano. Choose your leather.

Sistem Khaki

Artisanal Note

"This model requires a precise 20mm lug width to preserve the original sartorial balance."

Technical Specifications

Swatch YIS407G
Lug Width
20 mm

The essential strap measurement.

Browse 20mm straps →
Reference

YIS407G

Movement

Swatch caliber Sistem51 Date

The Heritage

The Sistem 51 was introduced by Swatch in 2013 as the first automatic mechanical movement composed of just 51 components. It features the Sistem51 caliber with date indication, characterized by an entirely automated construction. The case has dimensions of 42mm with welded crown and caseback to ensure water resistance.

FAQ

What is the lug width of the Swatch Sistem 51 YIS407G?

The lug width of the Swatch Sistem 51 YIS407G is 20 millimetres. This measurement represents the internal space between the two lugs of the case and is essential for selecting a compatible strap. To verify it, measure the lug width directly or consult the model's technical documentation. A 20mm strap ensures a precise fit without lateral play.

What is the best strap for the Swatch Sistem 51 YIS407G?

The choice of strap depends on intended use and desired aesthetic. A vegetable-tanned leather strap imparts formal elegance and develops patina over time. NATO straps emphasise the sporty and casual character of the model. Vulcanised rubber straps offer absolute versatility and water resistance. For those seeking balance between elegance and functionality, we recommend a calf or alligator strap with vegetable tanning.

How do I change the strap on the Swatch Sistem 51 YIS407G?

To change the strap, you will need: a spring bar tool and a stable work surface. Position the watch with the lugs facing upwards. Insert the tool into the grooved end of the spring bar and apply gentle pressure to extract the spring. Repeat on the opposite lug. Remove the old strap and insert the new one, ensuring the spring bars are fully seated in the new lugs. The operation requires precision to avoid damage to the case.

Is an aftermarket strap compatible with the Swatch Sistem 51 YIS407G?

Yes, any strap with a 20mm lug width is compatible with the Swatch Sistem 51 YIS407G. The model uses standard spring bars, allowing replacement with high-quality artisanal straps. Milano Straps offers a selection of 20mm straps in leather, NATO and rubber, designed to fit this case perfectly and many other models. Always verify the correct lug width before purchase.

How long does a leather strap last on the Swatch Sistem 51 YIS407G?

A quality leather strap, made with vegetable tanning, typically lasts 2-4 years with moderate daily use. Durability depends on intensity of use, climatic conditions and maintenance. Vegetable-tanned leather develops characteristic patina and becomes softer over time. To extend the life of the strap, avoid prolonged exposure to water and direct sunlight, and occasionally apply specific protective products. Once worn, the strap can be replaced easily whilst keeping the same case.