Carbon brush is consumable parts of all types of polisher or grinder. They need to be replaced when they are exhausted, otherwise polisher stop working. 1 Piece of 4" to 5" (110V, 5/8"-11 thread, 1000 Watt, side handle and handle, water feed system, GFCI circuit breaker, 3 extra pairs of carbon brush ) New Version Wet Variable Speed Polisher.
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