LifeSupplyUSA True HEPA Filter Replacement Compatible with Alen Air FLEX HEPA-PURE BreatheSmart Air Purifier

I thought this was okay at first, even though a review mentioned it wasn't quite right as far as fit.. I didn't realize why specific, expensive filters were required for my air purifier ~ nor did I understand the importance of the unique outer layer filter with its proprietary (?) material or design. If the black flap of material that velcros onto the box filter portion is a cheap, substituted material rather than an actual Brand filter or equivalent as the 1st stage filtration outer layer ~ dust particles are easily pulled into the box filter, %26 then passes through into the intake of your machine. A substandard filter won't last as long nor work as efficiently %26 effectively ~ and your air purifier is going to get loud while wearing out faster. I had 2 choices. I chose to buy American for faster delivery %26 because it was slightly less expensive. Definitely not worth it as it lasted maybe 1-2 months instead of 4-6 months as the manufacturer recommended filter