Aquaboon 2PP-10B,1Micron Big Whole House Water Sediment Filter, 10-Inch, Blue, 2-Pack Melt-Blown Polypropylene 4-layer graded density with a 1 micron nominal filtration rating Universal replacement for all 4.5-Inch x 10-Inch Big Blue filter cartridges Pair of 2 filter, individually wrapped