(By:-Alen Corp, AllenCorp) for use with Alen A350 and A350 Plus HEPA air purifiers This HEPA replacement filter fits the Alen A350 or A350 Plus air purifier and features enhanced activated carbon for better odor control The filter life is 6 to 9 months with HEPA filter efficiency of 99 97% - Buy Now or get More Info on Alen Corporation Housewares - Click Here To Order