The Hydrotech 41400008 is the original factory replacement sediment filter for the Hydrotech HT, HTF, 101, and 103 series reverse osmosis drinking water systems. It effectively removes dirt, and rust, and particles to protect the more expensive filters in your system. This filter is a vital component of your multi-stage reverse osmosis (RO) system and should be replaced once every 6 months, or sooner if you have particularly hard water. If you're not getting enough product water you should replace the pre-filter cartridges to maintain optimal system performance. The Hydrotech Carbon Prefilter 41400009 is the genuine replacement filter cartridge for a wide variety of Hydrotech RO systems, including the 1240 Series, E, M & Pro Systems, HT101, HT102, HT103 and HT123 Series Systems. Removes Chlorine, Taste and Odor. Cost Effective 41400009 filter fits HT and HTF Series Reverse Osmosis Systems, Blue End Caps. Replace every 6 months, or as needed