Generally speaking, vacuums use a belt to drive a brush roller which is an agitation device. There are different sizes of belts. However, almost all vacuum use one of the following 3 styles of belts: flat, round, or geared.
The type and condition of the belt that a vacuum uses affect the vacuum’s performance a lot. The agitation is very important with vacuuming, if you use the agitation properly, you almost use 70 percents of the cleaning ability of a vacuum. The flat style belt is going to stretch when you use the vacuum, it may lose tension if you put the vacuum up to rest in the closet.

Usually, the flat style of belt runs in a circular fashion, this style allows manufacturers to run the belt off of one side of the brush roller, instead of the center where all of the dirt is. This is really a good design, because you can avoid premature failure due to the dirt and soil in the belt path.

About the round style belt. It is easy to produce and engineer, so it is considered to be the easiest type of belt. The round style belt commonly runs in the same space as the dirt that has been vacuumed. This means the staples, hair, and dirt the vacuum pick up will pass around the belt; cutting, nicking, or even scratching it along the way.

The geared style of vacuum belt, which is also known as a positive brush system, is the most efficient way to drive a brush, it is considered to be the best belt style for vacuum. Since the brush get direct energy from the brush motor, it makes the vacuuming with higher cleaning efficiency. Because geared belts are commonly used on two motor vacuums, the cost of the vacuum that use geared style belts are more expensive.