Carbon Activated Pre-Filter for use with the germguardian FLT5000/FLT5111 HEPA Filter, for AC5000 Series Air Purifiers, Filter C, Pack of 4 4-PACK CARBON ACTIVATED PRE-FILTERS: Made in the USA From All-Filters Brand filter media THESE PRE-FILTERS ARE DESIGNED TO FIT: Germguardian FLT5000/FLT5111 True Hepa Filter C, For all AC5000 Series Purifiers CARBON ACTIVATED PRE-FILTERS: Extend The Life of The HEPA Filter and Remove Common Household Odors EACH CARBON FILTER: Measures 4.8"x19.25" MADE IN THE USA All-Filters UPC 0727908035001