Model RO2050 is OMNI's reverse osmosis water purifying and filtration system that fits easily under your sink. The RO2050 not only filters your water, but actually filters, then purifies, then filters your water again. The OmniFilter RO2050 removes calcium (hardness) and dissolved salts i.e. sodium, magnesium, iron salts, etc. In essence the Omni Water Filter RO2050 uses the best technology available for home purification - More than just a water filter.