Feature:1. 21700 Battery Charger: Compatible with 21700 lithium batteries (not contain 21700 batteries), each battery slot is charged and tested separately, the charging is automatically terminated after the battery is fully charged (note: please pay attention to the positive and negative poles).2. Large Capacity: 8x21700 batteries (excluding batteries), dual USB power bank, which can charge two devices at the same time, 3 input ports, any USB cable can charge the mobile power supply.3. Convenient to Use: The battery box of power bank is small and light, easy to carry, simple to install and unload, convenient and practical.4. LCD Screen: Accurately display the power, master the battery status at any time, plug and play, use USB port for power output, plug in the data cable to achieve portable charging at any time.5. Widely Used: It is compatible with all types of phones for charging, has a wide range of uses and is a necessary gift for you.Specification:Item Type: DIY Power BankBox KitMaterial: ABSGross Weight: 191g / 6.7ozColor: BlueBattery Type: 21700 battery x 8 (not included)Interface: 5V 2.1AOutput Port: 2 x USBInput Port: Micro Type CScope of Application: all models of mobile phones can be charged.Package List:1 x Battery Box(Battery Not Included)1 x Screwdriver7 x Screw