The purpose of the air gap faucet [thumb-handle] is not only to deliver drinking water from the RO unit, as all faucets do, but also to provide an "air gap" for the RO unit's drain system. An "air gap" is a siphon break to assure that drain water cannot flow backward from the household drain system into the reverse osmosis unit.
Elegant RO water filtration faucet for kitchens. Faucet reverse osmosis option is major upgrade from standard filters. Made of finest, heavy material. Order today!