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)AC/USB Desktop Battery Charger :
* Quick charge with automatic constant current control prevents battery from over charging, short circuit, and electronic shock.
* Charge your cell phone battery without the phone.
* Also work with OEM (original) battery.
* LED charging light indicator. Turn red in charging, turn blue when done.
* Input: AC 100-240V 50/60Hz 150mAh.
* Output: DC 4.2V 350mAh ± 50mA.
* USB Port Output: 5.2V 800mAh.
* Use this charger to charge the stock battery as well, swap one out when the other dies.
2)New 3400mAh Rechargeable Li_ion Battery:
* Brand: Unbranded/Generic .
* High quality Li-Ion battery.
* Battery Type: Lithium Ion.
* Battery Capacity: 3400mAh .
* Voltage: 3.8V.
* Best Replacement for the original battery with comparable standby and talk time .
3)Fish Bone Winder Rubber:
* Flexible and washable if need .
* Unique cable winder for organizing your earphone cord
* Compatible with Headphone Cable,Telephone.Cable, Mouse Cable,etc
* Size: 6.4 cm x 2.8 cm Material: Silicone
* Color:as shown in pictures.

• * For Samsung Galaxy J3 (2017) Battery Charger Accessories .
• * Package includes : New 3400mAh Rechargeable Li_ion Battery X 2.
• * Travel Dock USB/AC Charger X 1 ; Fish Bone Winder Rubber X 1.
• * Compatible with:Samsung Galaxy J3 (2017) SM-J327U ( Unlocked )
• * Accessory only, cell phone and earphone not included.

* For Samsung Galaxy J3 (2017) Battery Charger Accessories .SharpCost