Alc 40103 60/100 grit glass bead – 4 lbs. 4lbs medium, 60/100 grit, 0.015″, 5.0-6.5 mohs; used when a smoother, brighter or matte finish is desired; typically used in a blast cabinet or where the abrasive is being recycled; excellent choice for light cleaning, surface rust, corrosion or de-burring of aluminum and other soft metals; can be used for subtle glass etching projects; 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