Alc 40110 20/30 grit urea plastic – 25 lbs. 25lbs medium, 20/30 grit, 0.032″, 3.5 mohs; removes light surface rust or corrosion without etching the surface; excellent choice for cleaning, stripping and de-burring soft metals without generating much surface heat; typically used in a blast cabinet or where the abrasive is being recycled; produces very little dust and improves visibility in a blast cabinet; note: the size of the blaster nozzle should be three to four times larger than the grit size of the abrasive being used, the larger the nozzle size the more cfm of air is required