Disc brakes consist of several components. Which of the following is NOT part of a disc brake system?

A disc brake system is composed of various essential components that work together to slow down or stop a vehicle. Among these components, rotors, pads, and calipers play crucial roles:

• Rotors are the circular discs that rotate with the wheel and provide a surface for the brake pads to clamp down on, creating friction.

• Brake pads are the friction material that presses against the rotor when braking, generating the necessary force to slow the vehicle.

• Calipers house the brake pads and contain the mechanism that applies pressure to the pads against the rotors.

In contrast, drums are a component of a drum brake system, not a disc brake system. Drum brakes utilize a different mechanism where brake shoes press against the inside of a rotating drum to create stopping power. This distinction is fundamental in understanding the differences between brake systems, which is why identifying drums as not being part of the disc brake system is correct.