Crystal Quest Undersink Replaceable Single Fluoride Multi Plus Water Filter System CRYSTAL QUEST Single FLUORIDE REMOVAL Undersink Water Filter is stylish, convenient and effective. Contains fine-mesh pre-resin media (SIR-900) in the unit to reduce fluorides below 0.5 ppm. Capacity is up to 11,000 ppm with effluent levels below 0.2 ppm from 10 ppm feed. Installs neatly under the sink. Comes with attractive faucet & all necessary installation hardware. Easy to use and install on all standard sinks.