Features: Use the provided connector cable and connect the USB plug to any 5V power source. Connect the micro-USB plug to the DC Input socket of the charger base. Charger will finish self-checking after you connect this charger to power source, please wait for 3 seconds before you insert your battery in the charger. When the charger is powered, battery in Socket CHI, screen CHI lights on, Battery in CH2, screen CH2 lights on. The LCD display dual battery charger is compatible for Sony NP-F550 NP-F570 NP-F530 NP-F330, etc.