1 MICRON RATING: With a nominal filtration rating of 1 microns, our quality polypropylene sediment filter reduces sediment from the city and well water applications 20x2.5 NOMINAL: 20” slim filter made with melt blown spun polypropylene filter media QUALITY REPLACEMENT: 20" x 2.5" spun PP water filters, compatible with P1-20 / 155304-43 and SDC-25-2001 30-DAY GUARANTEE: SpiroPure filters have a 30-day money back guarantee. If you do not like the performance of your filter, you can send it back within 30 days of purchase. SP-P1-20 20x2.5 Melt Blown Spun Polypropylene 1 Micron Sediment Water Filter.