Qi-Infinity&trade; Powergrid 34200mAh External Battery Pack/High Capacity Power Bank charger for Laptops, Surface Pro 4/3/2, Surface book, Tablets and Smart Phones Monster capacity of 34200mAh. Provides 1 DC output for Laptops 1pcs SP3cable for Surface Pro3,4 and book and 2 USB ports for 5V USB-charged devices. Call it Grand Turk, Grand Panjandrum or whatever you fancy! Provides &gt;1 full charge to laptops or ~14 full charges to smartphones or ~30 full charges to iPod. Advanced Lithium Polymer super cells with &gt;500 recharge cycles. Solidly built, minimalist design, stylish and slim aluminum-body ensures good heat dissipation. The smart LCD display provides battery capacity and regulate voltage settings. It will automatically shutdown when there is an overload to protect your device 12 months of worry free warranty. Wide range of laptop connectors, Surface Pro/Pro 2/RT/ RT2 adapter, Lenovo X1 carbon adapter with adjustable 5 voltage levels (9V/12V/16V/19V20V) to charge most of the laptops. Also the maximum current output is 4 Amp so please check your device current ratings (usually printed on the back side) before purchasing. Most of the laptops (&gt;90%) are below that ratings. Note: Surface Pro 2 cable is not included. If you need to purchase compatible cable please go to buy yourself