17MM 18MM 19MM 20MM 21MM 22MM 23MM 24MM 26MM. 20/16MM LEATHER WATCH BAND STRAP FOR ROLEX DATEJUST 1601 16233 16013 LIGHT BROWN. 19mm Lug Width with 18mm Buckle Width (19/18mm Strap). 20mm Lug Width with 20mm Buckle Width (20/20mm Strap).