Strap for Tangomat GMT

The lug width of the Tangomat 635 is precisely 20 millimetres. This measurement is taken by positioning a digital calliper between the two lugs that hold the strap, excluding the watch case lugs themselves. It is possible to fit straps slightly wider (21–22mm) using adapters, but this would alter the proportions intended by Glashütte's Bauhaus design.

The choice depends on your intended use. For formal or executive settings, we recommend alligator leather with vegetable tanning in dark brown, or calf leather in burgundy-red. For a versatile sports-oriented approach, a NATO strap in light grey or sand accentuates the tool-watch character of the timepiece. For an elegant and evolving aesthetic, shell cordovan in burgundy-red represents the most refined solution, developing a patina that matures over time.

The strap is replaced by removing the two spring bars that hold the strap to the lugs. Use a spring bar tool to push the pin gently inward, creating space to extract it. Once the lugs are freed, the old strap slides off easily. Insert the new strap, aligning it perfectly with the lug holes, then reinsert the spring bars until you hear or feel the click of secure engagement. This process takes only a few minutes and requires no specialist tools.

Yes, the Tangomat 635 is fully compatible with aftermarket straps of 20mm width. Artisanal leather straps crafted by specialised ateliers—such as those made from vegetable-tanned leather, alligator, or shell cordovan—fit without difficulty thanks to standard spring bars. Always verify that the declared width is exactly 20mm to avoid adapters or aesthetic misalignment.

Longevity depends on material and frequency of wear. A calf strap with vegetable tanning, worn daily in normal conditions, typically lasts 3–5 years before requiring replacement due to buckle wear or leather weakening. Alligator and shell cordovan, being denser and more structured materials, can last 5–7 years or longer. The patina that develops over time is not deterioration, but rather the natural aesthetic evolution of the material.