[Mixed gravel]: Our rotary tool accessory - jewelry tool polishing brush has 6 different kinds of gravel, 6 different colors, and 10 pieces of each gravel to meet different needs. Green - 80 coarse sand, blue - 120 coarse sand, red - 220 coarse sand, gray - blue - 400 coarse sand, - 600 coarse sand, light green - 1000 coarse sand. [ and delicate design]: Unlike rubber wheels, open design can dissipate heat. Bonded mineral abrasives are much harder than most metals. [Parts with small pressure and perfect]: The flexible brush needs less pressure than the wire brush and conforms to the contour, even on complex parts. The bristle spacing is an ideal choice for removing coatings and other high-load substances. [Multi-purpose]: Radial brush is a concept used for metal processing, paint preparation, coating and anti-corrosion, applicable to aluminum, brass and bronze. [Flexible and safe]: The detail abrasive brush has very flexible bristles, which can remove the external " layer" without