AO Smith Whole House Salt-Free Water Softener, Single Stage NEW. Engineered to naturally reduce scale buildup on internal pipes and plumbing-salt and chemical free. Salt-free technology-no cleaning, backwashing, salt-bags or electricity required. Perfect for households of 4 or more people. Reduces scale buildup for 6-years or 600,000 gallons. For all your water needs-drinking, cooking, showering and bathing-make it salt-free. City or well water-engineered to work with both. Easy to install with a 3/4 connection size. Includes one whole house Descaler, shut-off valve, hose adapter and nipple.