Anker PowerCore 5000 Portable Charger, Ultra-Compact External Battery with Fast-Charging Technology, Power Bank for iPhone, iPad, Samsung Galaxy and More 1 The Anker Advantage: Join the 50 million+ powered by America's leading USB charging brand. High Capacity: Contains 5000 mAh of power. Enough to provide over an entire replacement charge for iPhone X and Samsung Galaxy S9, or almost 2 charges for iPhone 8. Ultra-Compact: Remarkably small, tubular design slides easily next to your phone in any pocket or bag. Just 10cm tall and 3cm wide.