# Main components and functions

Pos | Part | Function
--- | --- | ---
1 | Spindle | Main rotating part of the drill.
2 | Spindle guard | Protects the operator from the rotating spindle. Provides the drill with coolant to the drill bit.
3 | Head | Transfers rotational torque and feed from the motor to the spindle.
4 | Feed cassette | Defines spindle feed rate. Measured in inches per revolution (IPR) or millimeters per revolution (mm/rev).
5 | Air logic | Operates the drill.
6 | Split gear | Defines rotational speed. Measured in revolutions per minute (RPM).
7 | Range gear | Defines RPM range.
8 | Vane motor | Supplies power and rotation to the spindle.
9 | Motor valve | Supplies the airflow to the vane motor and the emergency stop button.
10 | Start | Starts the motor and activates drill feed and rotation mechanism. The motor continues to run after the button is released. When spindle reaches the pre-defined drilling depth, it returns automatically to the starting position.
11 | Rapid advance (optional) | Activates rapid spindle feed. The spindle advances to the work surface faster than the regular feed rate but does not rotate. Releasing the button stops the spindle.
12 | Retract | Returns the spindle to the starting position at any time during drilling cycle. The motor switches off automatically after retract.
13 | Emergency stop | Switches off the motor, and stops the spindle at any time during drilling cycle. Once pressed, the emergency stop button locks in position. You must manually reset the emergency stop to restart the drill.