These are directions on how you can to find the firmware and baseband model (modem firmware) your iPhone is at the moment operating.
Press to launch Settings out of your Springboard.
Press to select General from the Settings Menu.
Press to select About from the General Settings Menu.
From the about screen you can find your firmware version under the Version label.
Scroll down and you can find your baseband version under the Modem Firmware label.
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