A Tiffany & Co Return To Tiffany Heart Tag Toggle Necklace. In 1969 Tiffany & Co introduced a key ring that was inscribed with the message “Please Return to Tiffany & Co. New York”. Each piece was assigned a unique registration number, ensuring that if the owner ever mislaid their keys, they could be found at the flagship Fifth Avenue store in New York. Inspired by these iconic key rings the Return to Tiffany collection is now a classic part of the Tiffany & Co brand. The engraved front toggle closure on this necklace provides an extra focal point to the heart shaped charm.