The founder of KT Corporation coined and trademarked the term "CTO", which stands for Chlorine, Taste and Odor. Today, "CTO" is used by nearly every company in the world to describe the aesthetic capabilities of common carbon block filter elements. It is even used to describe the machines used to make these filters (“CTO extruders”, also invented by the founder of KT Corporation). But CTO filters are insufficient in the modern world where many municipalities have switched to using chloramine disinfectants or where filters are used on well water contaminated with foul-tasting sulfide or where surface waters are contaminated with musty organic chemicals from the decay of organic debris.
To meet these challenges, we have moved to a new standard –- "STOCC".
STOCC filters meet the full spectrum of aesthetic challenges. They control all forms of aesthetic contaminants no matter what the source of the water (municipal, groundwater, or surface water). A STOCC filter intercepts Sulfides; chemicals that contribute to Taste; rust sediment, dirt and Turbidity at NSF STD 42 Class 1 levels (0.5 micron); Odors; Chlorine; and Chloramine (i.e. the common disinfectants now used by municipalities). STOCC filters establish a new standard in comprehensive aesthetic purification of drinking water. What emerges is pristine, super-purified water. No off-tastes, no off-smells, and crystal clear... no exceptions.