Anker Astro E4 Manual Del Usuario página 5

The Astro E4 external battery is fully compatible with all USB adapters.
Reference the chart below for the charging times of different speed adapters.
If you purchased the version with an included USB adapter, the recharge time
is 6-7 hours.
USB Adapter Charging Speeds
Adapter Current Output Charging Time
5V / 2A 6-7 hours
5V / 1.5A 8-10 hours
5V / 1A 13-15 hours
5V / 0.5A 25-28 hours
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