Note: There is no mobile power comes with the backpack inside!,If you want to use External USB Charge Function, you have to do as follows:,1.Buy a mobile power,2.Connect your mobile power with the USB interface inside the backpack,3.Connect your phone with the USB interface outside the backpack,4.Charging begins.,There are 2 kinds of mobile power in the market:,1. Plug in your phone, you can start charging.,2. Plug in your phone also need to press button of mobile power then start charging,To cope with this backpack, we suggest purchase of the first mobile power.,3 Main pockets + 9 Inner small pockets + 2 Sealed Side pockets,Provides a separated space for your Laptop, iPhone, iPad, pen, keys, wallet, books, clothes,bottle and more.,Dimensions: 48*28*18cm ,Suitable Laptop Size: Less than 17 Inch,Capacity: 20-35 Litre,Color: Black, Blue, Grey, Purple,Material: Canvas,Applicable Gender: Unisex,Teenagers, Students,Handle/Strap Type: Soft Handle,Package Includes: 1 x Backpack