The Inspire 2 Intelligent Flight Battery Charging Hub charges up to four Intelligent Flight Batteries simultaneously. The Charging Hub will intelligently charge batteries in sequence according to battery power levels from high to low, if batteries are not paired. Pairing can be carried out using the DJI GO app. The Micro USB port is used for firmware updates.* Visit the Official DJI website and download the Inspire 2 User Manual for more information on how to pair batteries using the DJI GO app.