A: There are two kind brushes we normally use: the metal brush and carbon brush. We choose based on the speed, current and lifetime requirements. For quite small motors, we only have metal brushes while for big ones we only have carbon brushes. Compared with metal brushes, the lifetime of carbon brushes are longer since it will reduce the wear on the commutator. But for low speed motor, the carbon dust might not be able to burn in time which will cause failure too.
Q: Could you send me a price list?
A: For all of our motors, they are customized based on different requirements like lifetime, noise, voltage, and shaft etc. The price also varies according to annual quantity. So it's really difficult for us to provide a price list. If you can share your detailed requirements and annual quantity, we'll see what offer we can provide.