ARCTIC Power Bank 4000 is a portable power bank with an integrated 4000mAh Lithium-Polymer rechargeable battery ready to charge up your Tablet and Smart Phones. Roughly the size of an iPhone 5, ARCTIC Power Bank 4000 has an elegant yet modern Brushed Aluminum Surface and is only 0.4" thick so you can bring them just about everywhere. Keeping your mobile devices charged while enjoying the envious look from bystanders! ARCTIC Power Bank 4000 is not just for your Tablets and Smart Phones; it can charge practically any USB-powered devices, including Bluetooth headsets and wireless speakers as well. Smart charge level indicator shows you how much charge power is left so you can always keep your mobile devices charged when needed. An intelligent charge controller extends the battery life and a protection IC protects your mobile devices from short-circuit, over-voltage/current. ARCTIC Power Bank 4000 features a 3-year standby time so it is always ready when you need the extra power. ARCTIC Power Bank 4000 comes with a 2-year limited warranty. Please contact Arctic for service details at arctic.us@arctic.ac.