NOTE: They are blank tag with no pre-programmed serial numbers. Before you can use it, you need to write data through a 125khz RFID read/write device in order to read the ID serial number.
The chip is readable/writable/rewritable. It can be erased and written 100,000 times.
Applications: intelligent door locks, access control systems, time and attendance devices, hotel key cards.
Round sticker on the back for attaching to other items (cannot attach to metal).
Note again that the data cannot be read until the chip is programmed.