There are similarities in the way the Ultra Filtration and the Reverse Osmosis work; they both are removing total dissolved solids in the water. By removing the total dissolved solids you improve the taste and health benefits of the drinking water. Reverse osmosis systems use cross filtration and the Ultra Filtration system uses standard filtration. Standard filtration is where the contaminants are collected within the filter media. Cross filtration is where the water crosses the filter with two outlets; the filtered water goes one way and the contaminated water goes another way. The Ultra Filtration does not discharge wasted water down the drain like the reverse osmosis system does. There are many advantages to this; water savings, no drain needed,, use on refrigerators with water in the door. It uses the supplied water pressure instead of the pressure assisted metal bladder tank.