LS Accessories 1450 mAh Batteries for HTC Thunderbolt (ADR6400L) with Free Universal Charger with USB port Compatible with HTC Thunderbolt (ADR6400L) 2 X 1450 mAh high quality Lithium Ion batteries that charges to its full capacity for over 500 cycles Grade A batteries with Dual IC protection to ensure safety; Battery Voltage: 3.7 Volts Battery Energy Content: 5.37 Watt Hours Universal Charger with USB Port that can charge your battery and cell phone at the same time Charger Input: 100-240V, 50/60HZ, 0.1A; Output: DC 4.2V, 300mA; USB Output: 5.2V 500mA