Integrated digital display clearly shows remaining power, so you know when to recharge. Nonsolder design enables easy battery maintenance and replacements. Durable ABS construction securely houses unprotected flat 18650 batteries (not included) in precise alignment for reliable electrical connection and performance. Reliably charges smartphones and tablets during outdoor activity, business trips, or emergencies such as power outages with this compact powerbank shell. Build your own capacity powerbank with this 3slot 18650 battery case, featuring easy assembly and replaceable cells for extended usage. Use scenarios: Outdoor activities: camping, hiking, or other trips where power access is limited and you need to keep a phone or small device charged. Business travel: a compact, modular solution that fits in a bag or briefcase and provides onthego charging. Emergencies and outages: quick cell replacement supports continued operation of essential devices during power outages or remote work situations.