The AMX FX20-RF 3-in-1 200mm Replacement Filter Pack is a great way to service your AMX FX20 200mm 3 Layer HEPA Filter Box. It comes with 3 replacement filters that offer high-efficiency filtration and is easy to install. The pack consists of a Primary Filter, an Active Carbon Filter, and HEPA 12 Filter for high-performance protection. Each 200mm sized filter fits into the AMX FX20 Filter Box whenever ventilation maintenance is needed.