Also known as variable speed V belt.
The relative height (the ratio of the thickness to the bandwidth) is 0.3. According to its top and bottom with or without teeth, can be divided into non-tooth width V belt, internal tooth width V belt, internal and external teeth width V and truncated cone width V with four.
It is usually used in power transmission of belt type continuously variable transmission. Because of its simple structure, easy to manufacture, smooth transmission, can absorb vibration, easy maintenance, low manufacturing cost and so on are widely used and rapid development.