General information: The package contains 5 NTAG215 NFC cards, with NTAG215,50 x 30 mm chips, 504 byte memory.1 - 5 cm reading and writing distance, 100,000 times, erasable Can be deleted and edited repeatedly or can be set as read-only tag. If it is set to read-only, it cannot be modified or reset. Application fields Rewritable NFC cards are made of durable waterproof PVC material,can be positioned outdoor or near water without the risk of losing functionality. It can be used for, advertising, goods and smart authentication device, call request, SMS, action call, voucher and coupon, Bluetooth or Wi-Fi coupling, Handover shelf connection, electronic product authentication mobile companion, labels, labels and business cards, Suitable for all nfc mobile phones. Simply place the phone on the NFC 215 cards and the data will be sent directly to the phone without need of internal energy, battery, manual coupling, which is convenient and fast, can also be compatible and programmable with all NFC enabled mobile phones and devices. Note Since some cell phone models do not have NFC functions, they cannot scan NFC tags, it is not a problem with tags, please understand it clearly before buying Attention: these NFC tags are not designed for use on metal surfaces since metal would affect induction frequency.