This AUKEY 10,400mAh Portable Charger with Qualcomm Quick Charge 2.0 drops from $24.99 to $19.99 to $12.99 when you apply the code AUKEYPOW during checkout at Amazon. Shipping starts at $4, but is free using an Amazon Prime account. However, even without Amazon Prime, this is still the lowest price we could find for one of these chargers by $8. These chargers can fully charge an iPhone 7 three times or a Galaxy S7 twice. They also have built-in safeguards against excessive current, overheating, and overcharging, and Qualcomm Quick Charge 2.0, which offers over double the regular charging speed in Quick Charge enabled devices. Sales tax is charged in most states.