The MCAS (Multiple Chamber Air Sterilization) units are designed to remove or kill all nuclear, biological, and chemical agents. All MCAS units include a HEPA filter, Activated Carbon Filter, TEDA Carbon filter, and Ultraviolet Radiation sterilization, and AC or DC air blower.  The MCAS 120 and MCAS 600 use the same stainless steel filter housing. The MCAS 120 has one set of carbon trays and storage slots for two replacement set of filters.  The MCAS 600 has three carbon  trays and  spare filters are stored elsewhere.