Usage Tips:What You Get: 12 Pieces of Wire Bore Brush in 6 different sizes with 1/4 inch hex shank for general screwdriver holes. The and right amount of quantity of brushes for higher productivity when cleaning and polishing Premium Materials: Stainless steel and brass copper materials make the bore cleaning brushes . There is less chance of rusted when cleaning and polishing Size Guide: There are 6 sizes you can choose (8mm/0.31inch - 10mm/0.39inch - 12mm/0.47inch - 15mm/0.59inch - 17mm/0.67inch - 19mm/0.75inch) for your cleaning and polishing requirements Wide Application: The bore cleaning brushes in 6 sizes can reach narrow holes and confined areas easily. You can choose the brush sizes base on your needs to clean kitchen sink drain, machine holes, paint stains, or fine features without damaging surfaces Gentle Reminder: Please do not exceed 600 rpm and do not turn the bore brush counterclockwise. Use it as a gentle manual brush for better polishing results. Colour:Silver & Gold Material:Stainless steel Size:8mm,10mm,12mm,15mm,17mm,19mm Package Contents: 12 * Wire Bore Brush Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.