Features 504 BYTES MEMORY: This NFC card adopts NTAG215 chip, has 504 bytes memory, providing sufficient storage space to quickly write the desired information. LOCK FUNCTION: The NFC card has read write lock function, which can be repeatedly edited or read only. Cannot edit or reset after setting to read only. WATERPROOF: The NTAG215 card is made of waterproof PVC material and can be placed outdoors or near water without losing its function. HIGH STABILITY: The surface is smoothly and glossy, hard wearing, stable, odorless, and safe. Please rest assured to purchase! WIDE APPLICATION: The set contains 30 pcs NFC cards, which are compatible with all for Android phones and other devices that support NFC. Specification: Item Type: NFC Card Material: PVC Size: Approx. 22x30mm/0.87x1.18in Operating Frequency: 13.56MHz Available Memory: 504 Bytes Function: Read, Write, Rewrite, Read Only Package List: 30 x NFC Card Note: Not supported to use on metal surfaces. Package List 30 x NFC Card