The Inspire 2 Intelligent Flight Battery Charging Hub is designed for use with the Inspire 2 Battery Charger. It charges up to four Intelligent Flight Batteries simultaneously. The battery pair* with more stored power will be charged first. 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.