IWC Vintage Portofino Chronograph, Ref. 3731. Armbanduhr. 39x35x8, IWC Vintage Portofino Chronograph, Ref. 3731. Wrist watch. Stainless steel. Quartz-movement, calibre 630, working. Movement no. 2613149. Original leather strap with original pin buckle in stainless steel. Visible signs of wear on case and strap. Service papers enclosed, 02/2001. Papers enclosed, purchase 12/1989. Diameter ca. 35mm without crown.