Compact 18650 Battery Power Bank Case with LCD and Dual Output Turn standard flat-top 18650 cells into a portable power source with a compact, user-friendly battery case that provides real-time status and reliable output for phones, cameras, and small electronics. Key benefits - Converts commonly available 18650 flat-top batteries into a functional power bank for on-the-go charging and backup power. - LCD digital display shows remaining capacity and status for easy monitoring and better battery management. - Two output ports allow simultaneous charging of two devices, with stable 5V 2.1A maximum output for fast device charging. - Built-in intelligent input control protects battery health by managing charging and discharging intelligently. - Integrated dual-press electric light provides a simple built-in flashlight function for emergencies or low-light tasks. Main features - Smart input control system with two outputs for reliable, efficient power delivery. - LCD digital display for clear battery status and remaining capacity indication. - Dual-press switch to toggle the electric light on or off quickly. - Designed for flat-top 18650 rechargeable cells only; cylindrical batteries with protruding top terminals are not compatible. - Output specification: 5V 2.1A maximum. - Dimensions: 172 x 80 x 23 mm. Compatibility and battery requirements - Compatible with flat-top 18650 rechargeable batteries with nominal voltages in the range 3.2 V to 4.2 V. - Do not use batteries with damaged outer sleeves or batteries with raised top terminals. - Polarity must be observed when installing batteries. Practical use scenarios - Emergency phone charging during travel or power outages when you have spare 18650 cells available. - Field photography or outdoor activities to power cameras, lights, or mobile devices without access to mains power. - DIY power solutions for hobby electronics, testing, or temporary setups where modular battery packs are preferred. Troubleshooting and maintenance tips - If the LCD shows zero after installing batteries, connect and activate the case to initialize the display. - If the device being charged does not reach full charge, try a different charger head or cable; higher-power chargers supporting PD or QC protocols perform better. - The display may require calibration through 2 to 3 full discharge and charge cycles. Fully discharge to near 0 and then fully charge to 100 several times to stabilize displayed capacity. - Store and use the case away from high-temperature environments. Safety and handling precautions - Do not use batteries with damaged outer sleeves or exposed wraps. - Only use flat-top 18650 batteries; do not use batteries with protruding positive terminals. - Ensure correct placement of positive and negative ends when inserting batteries. - Do not expose the case or batteries to high temperatures during use or storage. What is included - Battery power bank case only; batteries are not included. Notes - Slight measurement variation of up to 0 to 1 cm may occur due to manual measurement. - Product color may vary slightly from images due to monitor differences. This description reflects the product specifications and functions accurately for informed purchasing and safe use.