Huawei GT3 Guide De Démarrage Rapide page 7

Getting started
Follow the instructions in the following figures to set up your phone.
Before you insert or remove the SIM card, power off your phone.
When using the SIM ejector pin, exercise caution to avoid
injuring yourself or damaging your phone. Keep the pin away
from children to prevent them from accidentally swallowing it
or injuring themselves.
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