Most new vehicles now come with an automatic transmission as opposed to the traditional manual version with a clutch. This mechanism uses a torque converter and many other elements to perform the function of switching gears without any additional input from you.
One part of this component is the filter. Positioned over the fluid intake, the automatic transmission filter stops debris from entering the pan. This prevents contaminants from polluting the inner workings, and it also guards against damage. Some models may include a mesh-style screen made of either nylon or metal instead of a filter.
The aforementioned fluid serves its purpose of cooling and lubricating the system as a whole. This enables the gears to shift easily. Flexible tubes known as cooler shoes transport the fluid through the oil cooler - which can also be called a heat exchanger.
Finally, the automatic transmission bands are tightened around a drum to stop any rotation. They are circular straps that are adjustable and lined with a material that causes enough friction to halt the process.