The sony bc trx battery charger is a spare charger for the sony rx1 digital compact camera the bc trx comes with a status indicator and is compatible with 7 types of battery including np bx1 np bn1 np bn np fg1bg1 np fd1bd1fd1 np fr1 and np bk1 batteries you can also use the usb charge function and supplied micro usb cable to power up the handycam camcorders and compact system cameras nex too