Horological Meandering

I am having a custom strap made for my Kollokium Variant F and I can’t seem to find the distance between lugs measurement. Based on the 40mm diameter, it should be 20mm. Anyone know the answer?

...but finally Belmont watches states this: New: Kollokium Projekt 01 - Variant "B" Dated: 2024 Limited: 199 Pieces Made Strap: Black elastic textile single-piece strap with “hook” buckle in die-cast steel Case Size: 40mm x 11mm thickness Lug Width: 20mm ... 

i suspect there’s zero difference between the Variant B and F. I’ll swing by a watch shop, just to be safe. Thanks for chiming in, I appreciate it!

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