ABC or MULTI-PURPOSE extinguishers utilize a specially fluidized and siliconized mono ammonium phosphate dry chemical. It chemically insulates Class A fires by melting at approximately 350F and coats surface where it is applied. It smothers and breaksthe chain reaction of Class B fires and will not conduct electricity back to the operator.Make sure of the safety of your vehicle with this red plated dry chemical (monoammonium phosphate) fire extinguisher. This ABC Rated unit is 2-3/4 diameter and 10 tall features an anodized aluminum head is rechargeable and includes a red powder coated steel mounting bracket Fire Extinguisher Ratings:Class A: For Wood Paper and Most PlasticsClass B: For Liquid and Gas FiresClass C: For Electrical Fires