GSM, or UMTS handsets, and will work in all three cases. In 3G networks, it is a mistake to speak of a USIM, CSIM, or SIM card, as all three are applications running on a UICC card. Usage Since the card slot is standardized, a subscriber can easily move their wireless account and phone number from one handset to another. This will also transfer their phone book and text messages. Similarly, usually a subscriber can change carriers by inserting a new carrier's UICC card into their existing handset. However, it is not always possible because some carriers (e.g., in U.S.) SIM-lock the phones that they sell, preventing rival carriers' cards from being used. The use and content of the card can be protected by use of PIN codes. One code, PIN1, can be defined to control normal use of the phone. Another code, PIN2, can be set, to allow the use of special functions (like limiting outbound telephone calls to a list of numbers). PUK1 and PUK2 is used to reset PIN1 and PIN2 respectively. The integration of the ETSI framework and the Application management framework of GlobalPlatform is standardized in the UICC configuration. References 3GPP standards Chip carriers