5 Extra Pairs of carbon brush are included in this package. Carbon brush is consumable parts of all types of polisher. They need to be replaced when they are exhausted, otherwise polisher stop working. This pack carries (a)-(d). Many other sellers DO NOT attach the lock ring. (b) 78 Pieces of 5 / 5 Inch Diamond Polishing Pad for concrete travertine granite marble quartz. 15 X Grit 50 100 200 400. 6 X Grit 800 1500 3000. (c) 2 Pieces of 5 Professional Grade Final Glaze Buffing Pad (they bring mirror like polished result to natural granite marble). (d) 1 X 5 aluminum backer/Pad Holder.