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　　The factory production of brush is used for all kinds of motor commutator or slip rings on the sliding contactor, it has a good electrical conductivity, thermal conductivity, lubricity and collecting the reversing function, and has certain mechanical strength, can according to user needs specifications and shape structure selection of processing and manufacturing. Can be divided into four categories: (1) natural graphite brush, (2) the resin graphite brush, attunements graphite brush, (3) (4) including the metal graphite brush. Targets JB2623-79 kinds of specifications, a total of 38 brush structure form of the BG.