Q5 is a type of configuration for Low Frequency RFID Tags operating at 125 kHz. The Q5 configuration offers the ability to rewrite the chip multiple times with user data. The EEPROM memory has 256 bits organized in 8 blocks of 4 bytes each.

The data programmed into the memory can also be protected with a password: without the password, the chip cannot be read or rewritten. This feature is particularly useful considering that the chip can be configured to "respond" only to a reader who provides it with the correct password.