Technical Archive

Nivada Grenchen
Antarctic 35002M20— lug 18mm

Nivada Grenchen Antarctic 35002M20: 18mm strap. Alligator, box calf, shell cordovan and rubber, cut and stitched in Milano. Choose your leather.

Antarctic 35 Black - White Luminova / Stainless Steel / Flat Link

Artisanal Note

"This model requires a precise 18mm lug width to preserve the original sartorial balance."

Technical Specifications

Nivada Grenchen 35002M20
Lug Width
18 mm

The essential strap measurement.

Browse 18mm straps →
Reference

35002M20

Movement

Landeron caliber 21 Hours, Minutes, Seconds

The Heritage

The Nivada Grenchen Antarctic 35002M20 is a 35mm stainless steel chronograph developed in the 1960s as a polar expedition instrument equipped with the manual-winding Landeron caliber 21 movement. Designed for scientific missions and extreme environments, the watch features a satin-finished steel case and requires an 18mm lug width strap. The Landeron caliber remains a benchmark for manual-wind reliability and maintainability across decades of use.

FAQ

What is the lug width of the Nivada Grenchen Antarctic 35002M20?

The lug width of the Nivada Grenchen Antarctic 35002M20 is 18mm. This measurement must be verified by placing the calliper on the inner shoulder of the lug, excluding the flanges that connect to the case. Precision in measurement is critical to ensure proper strap fit without gaps or mechanical stress.

Which strap is most suitable for the Nivada Grenchen Antarctic 35002M20?

The ideal strap depends on your intended use. For a formal approach, cognac brown alligator or burgundy shell cordovan complement the satin-finished case elegantly. For a functionalist aesthetic faithful to the model's polar expedition heritage, an olive-green NATO or black rubber strap echo its original character. Shell cordovan offers the finest balance between evolving patina and constructive compactness.

How do I change the strap on the Nivada Grenchen Antarctic 35002M20?

Strap replacement requires a spring bar tool. Carefully lift the strap lug towards the outside of the lug to release spring tension; the terminal of the spring bar will exit its seat and the strap will detach. Repeat on the opposite lug. Insert the new strap, aligning the holes with the lugs, and verify that the spring remains seated. On the inner lug shoulder, never force: gradual pressure ensures proper spring positioning.

Can I use an aftermarket strap compatible with 18mm lugs?

Yes, all artisanal straps with 18mm lug width are compatible with the 35002M20, provided you verify the inner shoulder width of the lug. Straps crafted from premium materials—alligator, shell cordovan, vegetable-tanned calf—will develop a natural patina that complements the evolving aesthetics of the satin case over time. Avoid straps with standard 20mm or 16mm lug widths.

How long does an artisanal leather strap last on this watch?

A quality leather strap crafted with vegetable tanning lasts approximately 5–8 years with daily wear, accounting for environmental exposure and cleaning frequency. Shell cordovan, owing to its compactness, can exceed 10 years. The patina that develops is part of natural aging: superficial creasing does not compromise mechanical integrity. Vulcanised rubber lasts longer but diminishes aesthetically after 7–10 years due to material rigidity.