30 piece wheel and cup brush box. Each bulk box includes: (8) 1-3/4? coarse cup, (2) 1-3/4? fine cup, (6) 2-3/4? coarse cup, (2) 2-3/4? fine cup, (4) 2-1/2? coarse wire wheel, (2) 2-1/2? fine wire wheel, (4) 3? coarse wire wheel and (2) 3? fine wire wheel. Radial wire wheels for cleaning in crevices and contours. Cup brushes for surface cleaning of large, flat surfaces. Heat treated steel wire.