Replacement filters for 6 Stage Reverse Osmosis systems - These filters fits all standard RO systems with 10" filter housings (open the housings to change the filter inside). Pre-filters in this pack are; 1 x Drop-In Sediment Filter (reduces sediment, silt, rust, and suspended solids down to 5µm), 1 x Drop-In GAC filter (reduces chlorine, VOCs, and pesticides), 1 x Drop-In Carbon Block (further reduces chlorine, VOCs, and pesticides) Post-Filters in this pack are; 1 x Inline Post Carbon Filter (polishes RO water to remove residual impurities, taste, and odour), 1 x Inline Alkaline / Remineral Filter (replaces health-essential minerals such as calcium and magnesium which are removed in the RO process) Vontron 50GPD RO Membrane; Removes over 1,000 contamniants down to 0.0001µm (micron). Vontron are one of the worlds' leading manufacturers of RO membranes The filters in this pack are not supplied with the male fittings required for the inline post filters. If you are replacing filters on a Finerfilters RO system you will need to retain the fittings. If you require these fittings they can be found by searching for the following 'ASIN' codes (starting with B0...) in the search bar above! Elbow Type; B07PFKT54V | Straight Type; B07PGQ7WCY