Nomos Glashütte
Zürich 805.S21— lug 20mm

The lug width of the Nomos Glashütte Zürich 805.S21 is 20 mm. This measurement is determined by the internal space between the case lugs and represents a deliberate proportion relative to the 39.90 mm case diameter and overall aesthetic design. To verify it, measure the distance between the two vertical lugs integrated into the case using a calliper.

The choice depends on intended usage. For formal elegance, we recommend vegetable-tanned calf leather (cognac brown or black) or authentic shell cordovan, which develops patina over time. For sporting versatility, a NATO strap in canvas and nylon maintains the rigour of German design. Brown alligator on vegetable tanning offers an excellent compromise between durability and visual texture.

The strap is anchored via spring bars on both sides of the case. Using a dedicated tool (spring bar tool), apply gentle pressure to retract the spring bar and slide the old strap upward. Insert the new strap through the lower lug, then release the spring bar allowing it to click into the upper seating. Verify that the strap is perfectly aligned before wearing the watch.

Yes, any strap with a 20 mm lug width is compatible with the 805.S21, since the spring bars are standard. However, ensure that the strap thickness does not exceed 4.5 mm near the lugs, so that rotational movement remains fluid and the case does not experience excessive lateral pressure.

A high-quality leather strap (vegetable-tanned calf, alligator, shell cordovan) lasts an average of 5–8 years with moderate daily wear, developing characteristic patina. Longevity depends on environmental factors (humidity, sun exposure), frequency of wear, and care (periodic cleaning, drying after moisture exposure). NATO fabric straps have superior durability (10+ years), whilst rubber requires replacement every 4–6 years.