1.[COMPATIBLE AIR PURIFIER MODELS]:Our FLT5000 Replacement Filter C is compatible with Germ-Guardian Air Purifier AC5000 AC5000E AC5250PT AC5350B AC5350BCA AC5350W AC5300B.NOTE:This is not a OEM product but compatible with G-Guardian replacement filter. Any use of the brand name or model designation for this product is made solely for purposes of demonstrating compatibility. 2.[H13 TRUE HEPA FILTER C]:The high efficiency FLT5000 HEPA air filters capture 99.97% of airborne particles and particles as small as 0.1 microns. The activated carbon prefilter absorbs smoke, cooking fumes and noxious odors from harmful volatile organic compounds. 3.[ACTIVATED CARBON PRE-FILTER]:The activated carbon pre-filter of filter collects dust,pet hair,and other large particles, while extending the life of the HEPA filter.Treated carbon take in volatile organic compounds from the air and reduces odors from smoking, cooking and pets. 4.[VALUE PACKAGS]:Package includes 2 x H13 True HEPA Filter C + 8 x Activated Carbon Pre-Filters. For the performance, it is recommended to replace the HEPA filter every 6-8 months, replace the activated carbon pre-filter every 2-3 months for the performance (depending on your usage and environment), and obtain higher filtration performance for long-term use.