Patek Philippe Ref. 1518 in Stainless Steel
The Patek Philippe Ref. 1518 in Stainless Steel watch is incredibly rare with only four in existence. This particular watch was issue No. 1. This watch is incredibly special because it is the first perpetual calendar chronograph and the only way made in stainless steel. This vintage watch was first created in 1941, and the steel models were the most complex to perfect. Due to the rarity and ingenuity of this piece, this watch costs $11 million.