CO2 Fire Extinguishers are engineered to effectively suppress fires through the use of carbon dioxide gas. Due to their non-conductive, non-damaging, and residue-free properties, they are particularly well-suited for environments that contain flammable substances and electrical equipment. Carbon dioxide (CO?) is a gas that is stored in liquid form under high pressure. For Class B (flammable liquids) and Class C (electrical) accidents. Ideal for sensitive apparatus, as it does not leave any residue.