BPM F-15 Assembly Instructions & Owner's Manual page 38

The interface of switching speeds
6.4 Assisted Power Select or Throttle Level Select
Press UP or DOWN to change the output power of the motor.
The power ranges from Level 1 to Level 5. Level 1 is the
minimum power. Level 5 is the maximum power.
The default level is Level 1.
The choice of motor power rate
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