Rosslare AT-ERC-26A-3001 125KHZ Proximity Read-Only Card (Formerly AT-R14C). This is a credit-card sized credential with RFID electronics built inside the card, including an integrated circuit and an antenna inside that can be printed for human-readable information using standard ISO card printers, which can be machine read using very low power wireless communications. Having no power of its own, it can be read by card readers when it passes through the electromagnetic field produced in the proximity of the reader. The range depends on the antenna and field generated by the reader, so the card will have different read-ranges.