1 Point 8 Kg Or 4 Lbs Ground Walnut Shell Media Abrasive 12-20 Grit, Or Blasting 12-20 Grit Crushed Walnut Shells, 4 lbs. Walnut media blasting is especially effective when you want to clean paint, grease and other dirt from the surface of a material but maintain the integrity of the substrate materials. Cleans and polishes glass, fiberglass, wood, plastic, stone and soft metals. For use with blasting or vibratory tumblers. It?s environmentally friendly and 100% silica free. ALLERGY ALERT! This media contains walnuts. 12-20 Course Grit Walnut Shell Abrasive Media for Tumbling, Vibratory or Blasting Walnut Shells Polish Surfaces without Damaging the Substrate 100% Crushed Walnut Shells Use Low Pressure 20-60 PSI for Soft/Sensitive Materials. Exceeding 80 PSI Lowers the Longevity of the Walnut Shell Media. Environmentally Friendly.