Features:A DIY power back case, can charge 4pcs 21700 batteries (Batteries need to be welded, and not included) Support full protocol fast charging 22.5W, two-way PD fast charging 20W. 22.5W output supports PD QC- AFC SCP- multi-protocol fast charging for laptop phone universalYou can take it on the plane without declaration, safe and reliableTransparent body, imported high-quality LED screen can check the remaining power in real-time Specifications:Item:for 4pcs 21700 Battery Charger Box Material: ABS-PVCColor: Gray/Golden/ SilverSize: approx 154x65x29MM Input: 5V / 2.1A/ 20WOutput: 5V/2.1A/ PD22.5WQuantity: 1 PC (Not includes the battery and charging cable) Note:1.Transition: 1cm=10mm=0.39inch2.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid.3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Package includes:1 PC x Charging Case