Each printed sheet product includes a core of flexible, microvoided polymer sheet material and a planar RFID assembly encoded with a unique electro/magnetic code permanently and integrally joined together with the core. The microvoided sheet material collapses around the core so the sheet product remains planar. Scoring defines one or more individual identification elements removable from a remainder of the sheet product that include at least a first element with RFID assembly but only part of the core. A separate magnetic strip storing its own unique data magnetically can be provided on the first removable element even at least partially overlying the RFID assembly for independent identification operation.