Fire Extinguishers - These units contain specially fluidized and siliconized mono ammonium phosphate powder, which smothers and breaks the chain reaction on Class B fires, fuses and insulates Class A fires and is a non-conductor of electricity. Non-toxic. **Standard J Hook Bracket is Included With All Extinguishers Except 2-1/2 lb. Which Comes With Marine/Vehicle Bracket**