To signal the **reverse maneuver** when there is no reverse light available, it is important to use hand signals to warn other drivers and pedestrians. The correct way to do this is to **extend the left arm with the palm of the hand facing backward**. This signal clearly indicates the intention to reverse, as it simulates the movement of going backward.

- The **reverse light** is a white light that automatically turns on when the vehicle begins to reverse, but not all vehicles have it. It is mandatory for most cars, but not for motorcycles, and it is optional for some three-wheeled vehicles and heavy quadricycles.

- In situations where this light is not available, such as in some older vehicles or motorcycles, it is crucial to use hand signals to communicate the reverse maneuver effectively and safely.

Therefore, when there is no reverse light, extending the left arm with the palm facing backward is the appropriate way to signal this maneuver.