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