It is made for IWC watches which has 21mm lugs. 17MM 18MM 19MM 20MM 21MM 22MM 23MM 24MM 26MM. 18MM LEATHER WATCH BAND STRAP FOR IWC PILOT PORTUGESE DARK BROWN WATERPROOF. Strap is 21mm at lugs and 18mm at the buckle and you can interchange with the buckle.
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