LG TONE-T90Q Free Manuel D'utilisation Simplifié page 26

Symbols
Refers to alternating current (AC).
Refers to direct current (DC).
0
Refers to class II equipment.
Refers to stand-by.
1
Refers to "ON" (power).
!
Refers to dangerous voltage.
The output level shall automatically return to an output level not exceeding
RS1 when the power is switched off.
Connection and use of this communications equipment is permitted by the
Nigerian Communications Commission.
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