POWER: Switches the device on or off (LCD screen lights up or goes out)
VOLUME: Adjusts the sound volume or mute
STORAGE: Saves the current setting data of speed, torque, auto reverse and root tip
limit value into program
APEX SETTING: Sets the root location (in M4 mode, file will be auto reverse when arrives the pre-set root location )
MODE: Switches the 5 operation modes
M1: Only root-canal length measuring
M2: Only root-canal enlargement
M3: Reciprocating rotary motion
M4: Both root-canal length measuring and enlargement
M5: Both reciprocating rotary motion and length measuring