It is made for IWC Pilot Portuguese watches with 23mm lugs. 18MM LEATHER WATCH STRAP BAND FOR IWC PILOT PORTUGUESE TOP GUN CLASP D/BROWN WS. 17MM 18MM 19MM 20MM 21MM 22MM 23MM 24MM 26MM. It will fit watch with 23mm at lugs with 20mm at the buckle.
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