IWC 5251 Portofino Moonphase, IW5251, 18k yellow gold on a strap with a yellow gold tang buckle, Kurt Klauss' manual wind IWC caliber 9521 pocket watch movement, moonphase at 3 o'clock, small seconds at 9 o'clock, white enamel dial with black painted Roman numerals, sapphire exhibition caseback, diameter: 46mm, thickness: 9.5mm, sapphire crystal, water resistant, roughly 350 pieces are believed to have been made, Excellent condition with a minor mark with age on the moonphase dial as pictured, Very rare and hard to get, NO box or papers.