W&H Perfecta 900 Instructions For Use Manual page 29

Operating controls – Bistable operation
During bistable operation, the selected maximum speed is automatically reached during motor start .
he motor handpiece runs independently .
Deactivation of bistable operation: Press program button x 2 .

Press the button .
The LED illuminates .

Set the speed .

Start or stop the motor
handpiece by tapping the
pedal or flap .
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