The nice thing about this 19v laptop solar charger is that if you don't have sun, you can still have portable power by charging up the
16,000mAh internal battery in a wall socket and waltzing off to wherever it is you need backup power. It just takes less than 3 hours of wall charging to fill it up and the internal battery provides 3 - 5 hours of run time for your laptop with a full charge. solar charger for laptop
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