Nomos Glashütte
Ahoi 561— lug 18mm

The Nomos Glashütte Ahoi 561 is fitted with an 18.00 mm lug width. This measurement is determined by the distance between the case lugs and directly determines the compatibility of all aftermarket straps. Precise measurement—placing a ruler between the exact centres of the lug holes—is essential to avoid ordering errors.

Alligator is the most harmonious choice: its natural rectangular grain pattern dialogues perfectly with the quadrant's minimalist geometry. Shell cordovan represents an alternative for those who appreciate character evolution over time. For sports or marine applications, FKM (Viton) rubber resists moisture and salt without constructional compromise.

The process involves extracting the lug pins (two small metal cylinders passing through the case sideways). Use a dedicated hand tool—never a hammer or improvised implements—to gently lift the pin from its first notch until fully extracted. Repeat on the other side, then insert the new strap by aligning its hole with the first pin and push until seated. The operation takes less than one minute once familiar.

Any strap with an 18 mm lug width is compatible, regardless of brand or material, provided the holes are centred and aligned. Compatibility is universal at 18 mm. We recommend verifying that the strap thickness (base measurement) suits the case's internal lug height (approximately 5 mm standard).

A quality artisanal alligator or calf strap lasts between 5 and 8 years with daily wear and regular maintenance (damp cloth cleaning, annual conditioning with specific creams). Shell cordovan, due to its superior density, can exceed 10 years. Wear accelerates in chlorine-saturated or high-humidity environments. A durable cotton NATO strap typically lasts 3–4 years before showing seam fraying.