The **seat belt** is a crucial element for the protection of vehicle occupants in the event of an accident. Its main function is to keep people in their seats and prevent them from being ejected from the vehicle during an impact or rollover. For the seat belt to be effective, it must be properly adjusted to the body, neither too loose nor too tight.

- **Shoulder belt**: It should pass over the collarbone, between the shoulder and the neck, and go down the center of the chest. If placed incorrectly, such as over the neck or shoulder, it can cause serious injuries or slip, reducing its effectiveness.

- **Lap belt**: It should be over the hip bones, always below the stomach. Incorrect placement can cause serious internal injuries in the event of an accident.

The use of **clips or clamps** to loosen the belt can cause it not to fit properly to the body, increasing the risk of the belt not functioning adequately in an accident. This can lead to dangerous situations such as the "submarining effect," where the body slides under the belt, reducing its protective capacity.

For these reasons, it is essential not to use devices that alter the fit of the seat belt, as they compromise its effectiveness and the safety of the vehicle occupants.