2A 10BC Dry Chem fire extinguisher is UL rated 2-A:10-B:C and meets minimum code requirements for fighting wood, paper, fabric, flammable-liquid, and live electrical-equipment fires. The Class A size rating represents the water equivalency. Each number represents 1 ¼ gallons of water. For instance, 2A means the extinguisher is just as effective as 2 ½ gallons of water. The number 10 indicates that the extinguisher fights Class B fires as large as 10 square feet. It is safe for Class C fires. Class B fires are flammable liquids such as alcohol, ether, oil, gasoline and grease, which are best extinguished by smothering. Class C fires are energized electrical equipment.