LS Accessories 1450 mAh Battery for HTC Thunderbolt (ADR6400L) Compatible with HTC Thunderbolt (ADR6400L) 1450 mAh high quality Lithium Ion battery 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