This style of deionizer consists of two media tanks in series. The first tank contains cation resin in the Hydrogen (H) form and the second tank contains anion resin in the Hydroxyl (OH) form. Typical treated water quality is in the range of 50,000-250,000 ohm resistivity depending on feed water chemistry and 1,000,000 to 2,500,000 ohm resistivity with R.O. water as a feed. These units are designed to regenerate with chemicals DIRECTLY FROM THEIR SHIPPING CONTAINERS—NO HANDLING REQUIRED. Chemicals used are 30% Hydrochloric (HCl) acid and 50% liquid Sodium Hy-droxide (NaOH). Systems are fully automatic with regeneration initiated by a field adjustable resistivity meter. A manual override is included to allow the operator to finish a “run” without interruption.