ABC Dry Chemical Fire Extinguisher, with Wall Bracket. Screen Size 4.7 Inches. Amerex ABC Extinguishers effectively fight Class A, B, and C fires and are a popular choice for offices, warehouses, homes, and more. Steel cylinders and all-metal valves make these rugged, dependable extinguishers. They are easy to maintain and service, making them an economical choice too.ABC Dry Chemical, Class A:B:C Extinguisher. For use on Class A (ordinary combustibles), Class B (Flammable liquid) spills or Fires involving live electrical equipment (Class C). All metal valve construction, Aluminum Valve. 20 x 20 x 29 inches.