Archimede Klassik

Most Archimede Klassik references take a 20 mm watch strap: 18 of 32. The lug width follows the case size: 36 mm case → 18 mm, 39 mm case → 20 mm and 42 mm case → 20 mm.

Shop 18 mm Shop 20 mm

Archimede Klassik lug width by case size

32 references measured. Updated 2026-10-30.

Case	Lug width	References	Watch strap attachment	For example
36 mm	18 mm	11	—	UA4929-A3.11, UA4929-A3.19, UA4929-A3.21
39 mm	20 mm	6	—	UA7969-A3.1, UA7969-A3.10, UA7969-A3.3
42 mm	20 mm · 18 mm on 3	15	—	UA7929-A2.1, UA7929-A2.1-SW, UA7929-A2.10

References that take a different watch strap

UA7939-C2.31: 18 mm, not the 20 mm of most 42 mm cases
UA7939-C2.42: 18 mm, not the 20 mm of most 42 mm cases
UA7939BM-C2.31: 18 mm, not the 20 mm of most 42 mm cases

Questions about the Archimede Klassik

Do all Archimede Klassik case sizes take the same watch strap?

No. The lug width changes with the case size: the 36 mm case takes 18 mm, the 39 mm case takes 20 mm and the 42 mm case takes 20 mm. Check your case diameter before you buy.