Dual-slot Charger: 1, Designed for Gopro Hero3/3 Battery, compatible with AHDBT-301/302 2, Input: DC5V, 1000mA; Output: 5V, 1-slot 2-slot total no more than 1000mA; 3, Can charge two battery at the same time.  Charging time: around 1.5H when only one battery inset, around 2.5H for two batteries together 4, The indicator light will be black out signal when the battery be charged full; 5, Can be powered with most standard USB chargers, the GoPro Wall or Auto Charger or a computer; Color: Black Compatible Battery Model AHDBT-302 Fits Camera Models GOPRO HD HERO3 HERO3 Decode Status Full-Decoded Battery Type Li-ion Voltage 3.7 V Actual Capacity 1300 mAh Other Features- Built-in imported A grade large capacity cell, provide long working life, good quality; Preventing over - charging and over - discharging, limiting current and short circuit protection etc Package Included 1 x Dual Charger 2 x 1300mAh AHDBT-302 battery. USB Cable not included