These reverse osmosis membranes are designed specifically for use in the household with under-the-sink reverse osmosis systems. These reverse osmosis systems have all the important steps of filtration before the reverse osmosis membrane and after the reverse osmosis membrane. The reverse osmosis membrane is usually the most expensive consumable part of the reverse osmosis system and needs to be protected by inexpensive sediment and carbon filters. The sediment filter provides protection for the RO membrane by reducing the amount of particles in the feed water and reduces the risk of erosion on the membrane in reverse osmosis systems. The micron rating of the sediment filter can be 50, 25, 20, 10, 5 or 1 micron. With durable RO membrane housing, you can ensure that these filters and the membrane itself are not compromised by external factors.