10 micron rating: with a nominal filtration rating of 10 microns, our quality polypropylene sediment filter reduces sediment from city and well water applications 20x4.5 nominal: 20” bb (big blue) filter made with dual gradient melt blown polypropylene filter media quality replacement: comparable to sdc-45-2010 and other 20” x 4.5” spun pp water filters 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 for a full refund
