About This 1st Stage: 5 Micron sediment filter that can effectively remove rust, sand, and solid impurities in the water to protect the delicate UF membrane. 2nd Stage: State-of-the-art UF Hollow Fiber membrane that uses standard home water pressure to push water through a semi-permeable membrane. 3rd Stage: KDF media (or Kinetic Degradation Fluxion Media) with activated carbon. 4th Stage: Post Activated Carbon Filter. Adopting fine coconut shell activated carbon with ultra-micron aperture, this carbon filter absorbs residual chlorine, organics, humus, and odor. Overview Material : Plastic Item Weight : 3.17 Kilograms External Testing Certification : NSF Product Benefits : Removes impurities, sediment, and bacteria; extends carbon filter life; improves water taste and odor Removes impurities, sediment, and bacteria; extends carbon filter life; improves water taste and odor Brand : iSpring