Features: Tip: 21700 batteries is not included in the package, you need to purchase separately. Can only use the 21700 battery of which positive electrode is flat top. Due to detachable design, the structural design is currently not foolproof. Once the positive and negative terminals of the battery is reversed, there is risk of the motherboards and protective board burning out and causing a fire. Please pay attention to the direction of the positive and negative poles. Experience easy assembly with our 21700 battery case, design to accommodate 6batteries for most power storage and featuring PD100w super fast charging capabilities. Specifications: Component:Plastic Number of batteries:6x21700 batteries Option Color:Black,White,Green; Size:Approx.168x90x38mm/6.61x3.54x1.5inch Support Fast Charging Protocols:PPS/PD2.0/PD3.0/QC2.0/QC3.0/BC1.2; Package Includes: 1pc Battery Case(Battery not include) note: Please allow 1mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual item color.