The 3M Belt-Mounted Powered Air Purifying Respirator takes contaminated air and uses a motorized blower to force it through a filter/cartridge assembly, purifying the air and delivering it to the hood. The blower runs on batteries and is mounted to the user's belt, giving that worker greater mobility and the ability to operate in a wide variety of environments. To assemble your own custom-designed system, simply follow these four steps: Choose a Head Assembly; Choose a Breathing Tube; Choose a PAPR Assembly; and Choose a Cartridge/Filter.