PUK (Personal Unblocking Key)

Security Feature for Mobile SIM Cards

The Personal Unblocking Key (PUK) is a security feature for mobile SIM cards. It is used to reset a Personal Identification Number (PIN) that has been lost or forgotten. If a user enters the incorrect PIN code several times in a row, the SIM card will become PUK-locked, requiring the user to enter the PUK code to unlock and reset the PIN.