Zte Spro 2 User Manual page 16

CAUTION:
Do not try to remove or change the built-in rechargeable battery
in your Spro 2 by yourself. Doing so will violate the warranty
policy from ZTE. Contact customer service for support.
1. Plug the AC adapter into the power socket on your Spro 2
and then put the plug into an electrical outlet.
2. Disconnect the adapter when the battery is fully charged.
NOTE:
If the battery is extremely low, you may not be able to power on
Spro 2 even when it is charging. Allow Spro 2 to charge longer
and try again. Contact the customer service if you still cannot
power on Spro 2 after prolonged charging.
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