Innovative Products of America's 72 replacement brushes (36 steel, 24 brass, and 12 nylon, in sizes 8mm '#8211; 19mm) for Professional Bore Brush Set No. 8001 can clean bushings, ports, tubes, holes, channels, sockets, brake guides, cylinder head bolt holes, clogged EGR ports, corroded light sockets, transmission valve bodies, parts washers and more. An innovative 1/4" driver with locking-bit-head firmly secures the brush in the handle. Individual sizes can be purchased in a 3-pack.