Keep your reverse osmosis or under-counter water filter running smoothly with this case of 50 iSpring sediment filter replacement cartridges. These cartridges come individually wrapped, to stay neat and tidy until ready for use. With melt-blown polypropylene construction, these four-layer filters provide excellent performance and endurance.1 Micron5 Micron10 Micron20 Micron50 MicronFeatures:Box of 50Compatible with most Reverse Osmosis systems and under-counter filtersIndividually wrappedMade of 100-percent melt-blown polypropylene4-layer filtrationGood for water filters and aquariumsSuited for both city and well waterNot compatible with Rainfresh SystemsEach measures 2.5 inches in diameter x 10 inches high