Product review (1 stars): Exactly Half the price sticker price of the OEM, but more expensive per gallon and 40% of the useful life.  Avoid.
300 gallon capacity for $30 or $0.10 per gallon as opposed to the Actual OEM filter that is $55 for 750 gallons or $0.07 1/3 per gallon means this doesn't save you any money AND needs to be replaced more often.  So this product is not useful, avoid.  Quick shipping though.