Official Harry Potter Necklace Harry Potter Charm on a silver plated Necklace This necklace has been created using the official style guide from Warner Bros. The charm is approx 20mm in height and 16mm wide The Necklace is a silver plated snake chain which is 16 inches in length with a 2.5 inch extender chain This necklace comes on the official Harry Potter branded card packaging and shows the Warner Bros logo on the reverse The Carat Shop are the official licensed manufacturers of Harry Potter Jewellery on behalf of Warner Bros.