I have a MSI GP60 Leopard Laptop. I am looking for an external portable power pack to charge my laptop while I am on an airplane etc. All of the power packs that I can find have a maximum of 19 volts and 4.5 amps. The power cord that came with my laptop says it has an output of 19v/6a. Does anyone know of a power pack with an output of 6 amps or a power pack that would be able to charge my laptop?