Each filter purifies 1 Standard (750 Milliliter) bottle of wine. Through Selective Sulfite Capture, sulfites and histamines are filtered to reveal more of the wine's natural flavors and aromas. TO AIR, OR NOT TO AIR?.
The filters have definitely made a difference since I have an allergy to sulfites and would otherwise routinely have hives. So, they definitely work for me.
Given that one filter only clears one bottle of wine, when three of us have a bottle, it becomes expensive if we each have a glass every night at dinner.