Product review (3 stars): Be careful to read
I bought these and were advertised as a 4 pack. When they arrived, there were only 3. Upon contacting the seller, I was informed that the original ad said it was for only 3, since I can't see the original ad now, I have to to take their word for it. They offered to refund my money but I declined since it was apparently my fault. I have learned to read the ad closer as to what you're actually going to get. It takes 4 filters, not 3, so why would you only sell 3?