The Amerex B500 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 350 degree F and coats the surface to which it is applied. It smothers and breaks the chain reaction of Class B fires and will not conduct electricity back to the operator. What's in the Box.Amerex B500 ABC Chemical Class A, B, and C Fire Extinguisher with 12 to 18 Feet Range (5 Lb, 3-Pack). F There are product categories which are not returnable due to hygienic or sanitary as required by manufacturers. In an event where there is an error regarding a price error or description, we will notify you ASAP. Items removed from their'blister-pack' display packaging are non-refundable.