Yoyos function as a fastening of ID-card or key fob on clothing. The extendable nylon string makes a use of the ID-medium possible despite it being fastened to the clothes. To attach cards to the yoyo, an ID-card container with hole or a punched hole directly in the card is needed. Plasticard-ZFT is happy to offer hole punching for your cards. Because especially with RFID-cards a secure and automatic hole punching done by the producer is advised to ensure the functionality of the RFID-antenna.