• Alen BreatheSmart FLEX/45i Replacement Prefilter 4-Pack
  • Alen BreatheSmart FLEX/45i Replacement Prefilter 4-Pack
  • Alen BreatheSmart FLEX/45i Replacement Prefilter 4-Pack
  • Alen BreatheSmart FLEX/45i Replacement Prefilter 4-Pack

Alen BreatheSmart FLEX/45i Replacement Prefilter 4-Pack


Product Description
The pre-filter covers the exterior of your purifier's air filter to capture larger particles such as dust and hair. Pre-filters are an important way to keep your purifier working efficiently and to extend the life of your air filter. For customers who prefer to replace dirty pre-filters instead of cleaning them, pre-filter 4 packs are ideal option.
  • Extends air filter life
  • Keeps purifier running efficiently
  • Pack of 4 prefilters
  • Designed for the BreatheSmart FLEX purifier and 45i purifier
Filter Subscription
One-time Purchase
Subscribe & Save 5%
$19.99 $18.99

Ships Free on Monday

Frequently Asked Questions

  • My Room is Bigger than the Listed Coverage Area of the Unit I Want. Will it Still Do Some Good?

    The efficacy of an air purifier is typically measured in air exchanges per hour, or how many times within an hour the air in a room is completely replaced. A rate of six exchanges per hour or more is considered very good and would meet our standards. If your square footage exceeds the listed square footage for your air purifier, it can still clean your room, but the rate at which it can do so decreases. When the air exchanges per hour drop to a certain point, you won’t be receiving all of the benefits of allergen-free, breathable air. For optimal performance, a good rule of thumb is to find an air purifier that can cover more than the square footage of your room.

  • My apartment is 1500 square feet total, with a living room and a bedroom. Will one air purifier certified for 1500 square feet meet the needs of my entire apartment?

    Although your air purifier may still do some good in your entire apartment due to natural air circulation, air purifiers work best in the room they’re placed in. Air purifiers can’t work through walls or doorways, nor can they typically travel up stairs for loft-style apartments. It’s best, then, to get two smaller units and place one in each room. If you can only get one air purifier, place it in the room where you spend the most time, as this is the room that will see the most reliable results. We usually recommend the bedroom, since air quality and allergies can often drastically affect your quality of sleep. Your air purifier is portable and can be moved from room to room as needed, too.

  • What Is the Difference Between Your Pre-Configured Air Purifiers and Your Customizable Options?

    If you’ve already done your research and you know exactly which purifier and air filters are right for you, then our customizable options will allow you to configure the air purifier that meets your exact specifications. If you’re still a bit lost, our pre-configured options are designed to take the guesswork out of compositing your own air filter from scratch. Each pre-configured option is designed with a different set of needs in mind, from allergies to pet odor, and it contains the specific combination of air purifier and air filter to fit the job. These options are still customizable from an aesthetic standpoint - you can still choose your own panels - but they are not otherwise customizable.