Are you looking for a flip phone that will suit your basic needs in a phone? look no further because here is the Sony Ericsson Z520 in Excellent condition and it is Unlocked GSM, which means you can use any standard SIM card of different carrier. This is also good to use when going out of the country because majority of the countries outside America uses GSM technology so they use SIM cards for GSM phones like this. this Sony Ericsson Z520 is also a Quad-Band and has a Bluetooth and camera. a perfect used phone to have.