**Arm signals** are a valid way to communicate maneuvers to other drivers, as long as they are performed correctly and are visible to other road users.

- **Visibility and correctness:** Arm signals must be made in a way that they are clearly visible to other drivers. This means performing them well in advance of the maneuver and ensuring there are no obstacles that impede their visibility.

- **Validity of signals:** Arm signals are even more valid than signals made with the vehicle's lights, as long as they are performed properly. This means that in situations where lights may not be sufficient, manual signals are a valid and effective alternative.

- **Types of maneuvers and signals:** There are different arm movements to indicate various maneuvers, such as changing lanes, braking, or reversing. For example, to turn left, extend the arm horizontally with the hand down, and to turn right, bend the arm upwards.


In summary, arm signals are valid as long as they are performed correctly and are visible to other drivers, making them an important tool for road safety.