The present invention aims to improve the durability of an RFID chip inlet. A module including an RFID chip amounted to an antenna is covered with polyimide film with an adhesive layer to make up an RFID inlet. The outer surface of the RFID inlet is then covered with the surface processed to increase surface lubricity of a base part. When the RFID inlet is for use in a rubber product, it is mounted to a rubber base of the rubber product, the exposed surface of the RFID inlet is covered with an unvulcanized rubber, and the unvulcanized rubber is then pressed and heated causing the RFID inlet to be embedded in the rubber base.