Aukey Quick 2.0 Charger
Aukey is another manufacturer that has a Qualcomm-certified Quick Charge 2.0 charger on Amazon, and it's also currently on sale for only $14.99 making it the cheapest we've seen yet. Chargers that are certified for Quick Charge 2.0 work just fine with the G4.
These are rather large chargers compared to some typical wall warts, but that's necessary to enable the faster charging rates.
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