5 MICRON RATING: With a nominal filtration rating of 5 microns, our quality NSF Carbon filter reduces fine sediment particles and chlorine taste & odor from tap water 40x2.5 NOMINAL: 40” filter made with CTO coconut shell carbon filter media NSF CERTIFIED: This filter cartridge is tested and certified by NSF International to NSF/ANSI Standard 42 for material requirements only QUALITY REPLACEMENT: Comparable to EP5-40 / 155815-03 and other 40” x 2.5” PAC (Powdered Activated Carbon) water filters SpiroPure SP-EP-40 40x2.5 CTO Coconut Shell Carbon 5 Micron Replacement Water Filter Cartridge