Important Safety Information: This product contains a blend of crystalline silica. Prolonged inhalation of this product may be harmful. IARC reports that there is sufficient evidence in humans for the carcinogenicity of inhaled crystalline silica in forms of quartz or cristabolite from occupational sources. Symptoms may not appear until permanent lung damage has occurred. Persons who use this product should have periodic physical examinations for silica exposure. Work areas should be periodically tested to determine the amount of airborne crystalline silica compared to OSHA and MSHA accepted standards. ALWAYS wear NIOSH-approved breathing protection for crystalline silica dust when working with product or when possible exposure to product dust exists. Users must comply with all applicable health and safety regulations relating to the safe handling of crystalline silica. See MSDS for information. California Prop 65 Warning: This product contains crystalline silica, a chemical known to the State of California to cause cancer.