QR code cufflinks with engraving on the black onyx, made of sterling silver. Surprise Your loved ones or friends a unique gift idea QR Code Cufflinks with Personalised Secret Message or a Link to Your favorite Song or Website. What is a QR code? A special bar code readable by QR scanners, mobile phones, tablets with a camera, and smartphones. Read more about QR codes on Wikipedia .
Each jewelry product above 5g must bear a hallmark. Hallmarks are granted by the State Assay Office.