PiPO M2 v.2 - Manual (Page 17)

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VII. VII. VII. VII. Battery Battery Battery Battery
Very Very Very Very Low Low Low Low Battery Battery Battery Battery Full Full Full Full Battery Battery Battery Battery Charging Charging Charging Charging Battery Battery Battery Battery
‘ ’ indicates that the power of Battery is full. When the battery level
becomes too low, a prompt comes up to note you to charge your
tablet.
While charging, you can check the charging status in the lock screen:
It takes around 5 hours to charge your tablet to full battery. Please only
use a 9V /2.5A adaptor included in the gift box to charge it.