4lbs medium, 60/100 grit, 0.015" particle size; suitable for a smoother, brighter or matte finish; works well in a blast cabinet or with recyclable media; light cleaning, surface rust, corrosion or de-burring of aluminum and other soft metals; suitable for subtle etching projects; note: nozzle diameter should be 3-4 times the grit size; larger nozzle needs more air cfm.