The Zimmermann Brake Kit - Rear - 138681 is a kit designed for cars to improve their braking performance. It includes a set of products that are specifically designed for the rear brakes of the vehicle. The kit contains three main components, which are not specified by brand name. These components are essential for maintaining and improving the braking system of a car. The first component is a set of brake pads, which are responsible for creating friction against the brake rotors to slow down or stop the car. The second component is a set of brake rotors, which are the discs that the brake pads clamp onto to create friction. These rotors are an important part of the braking system as they are responsible for dissipating heat and providing a smooth surface for the brake pads to grip onto. The third component is a set of brake sensors, which are responsible for monitoring the brake pad wear and alerting the driver when it is time for replacement. This kit is designed to provide all the necessary components for a complete rear brake replacement, ensuring safety and optimal performance for the vehicle.