Although, I'm yet to fully test this product - so far it's marvellous. I think I'll see how long it truly lasts today, but so far, it's not ran out after 2/3 charges of my phone. It's not highlighted in the product description, but there is a nice handy LED indicator to how much charge the device has, which is very nice. The two USB ports is a godsend,charging devices from PS Vita's to iPhones. It's perfect! It is a bit on the weighty side, but it's worth it for that extra juice.