You do not need a special back cover to use this batteryThis package is specifically designed for the cellphones we list here, if your cellphone is not in the list , then it's not for you.=============================================1)Universal USB/AC Charger:* This is an universal charger , which can charge virtually all smartphone li-on batteries in the market.* The top panel could be slided and the metal contact pins are also moveable.* You can slide it back and forth to fit virtually any size of Li-On batteries in the market.* You only need 2 pins to charge a battery.Here is the instruction:* To Charge the battery for Cingular Flip IV U102AA , allow the 2 metal pins on the charger to touch the 1st and the 3rd contacts of battery. * For other batteries, it's not necessarily to be the 1st and 3rd though, please refer to the user manual.* You should see the LED light turn blue on the charger, that means the contacts has been firmly connected.* Now you could plug in the charger with the battery into a power socket.* The LED Light will turn Red when charging the battery, turn blue to indicate the battery is fully charged.* Input: AC 100-240V 50/60Hz 150mAh.* Output: DC 4.35V 600mAh ¡À 50mA.* USB Port Output: 5.2V 1000mAh.2)New 1700mAh Rechargeable Li_ion Battery:* Brand: Sporting Persistence .* High quality Li-Ion battery.* Battery Type: Lithium Ion.* Battery Capacity: 1700mAh .* Voltage: 3.7V.* Best Replacement for the original battery with comparable standby and talk time .* Our battery is sent out with little or no power, so please charge it for about 6 - 12 hours before using.3)Micro USB Data Sync Cable ( 3 Feet/1M ): * Standard Micro USB Connector which could compatible with most devices that have Micro USB Port. * Type: USB 2.0 * New generic 2 in 1 Data/Charging USB Cable.