The strap is free of logos or markings. IWC Family 3719. IWC 3719-03. IWC 3719-28. IWC 3719-33. 17MM 18MM 19MM 20MM 21MM 22MM 23MM 24MM 26MM. Made from rubber, the strap is designed for durability. It is designed for a lug space of 15.5mm, while the shorter end has a lug width of 15mm.
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