You do not need a special back cover to use this battery
This package is specifically designed for the cellphones we list here, if your cellphone is not in the list , then it's not for you.
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100% Brand New.
1)New 3100mAh Rechargeable Li_ion Battery:
* Brand: Unbranded/Generic .
* High quality Li-Ion battery.
* Battery Type: Lithium Ion.
* Battery Capacity: 3100mAh .
* Voltage: 3.85V.
* The best spare battery for your phone.
* 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.
* Keep an extra battery on hand for extend standby and talk times.
* Integrated microchip prevents overcharging and lengthens battery life.
2)Screen Touch Pen
* Soft touch tip material prevents scratching to.the screen very smooth tip
* suitable for drawing,jotting notes,playing games and navigating on your device. * Lightweight copper body
1.Smooth Movement.
2.Lightweight body (5g)
3.Finger Pressure

• * Battery type: Li-ion; Voltage: 3.85V; Capacity: 3100mAh.
• * Package includes : New 3100mAh Rechargeable Li_ion Battery X 1.
• * Compatible with: LG Stylo 2 Plus K550 ( T-Mobile )
• * Accessory only, Cell phone not included.
• * High Quality,100% Brand New.

* Battery type: Li-ion; Voltage: 3.85V; Capacity: 3100mAh.ReelWonder