The dedicated faucet is the only visible part of a reverse osmosis system, so it gets chosen on appearance, and that is reasonable as long as three other things are settled at the same time. Once a hole has been made in a worktop or a sink, changing your mind about body type or reach is considerably more expensive than it was beforehand.
Matching the finish honestly
Brushed nickel is the most forgiving common finish: it hides water spots and fingerprints far better than polished chrome, which is the main reason it is popular in kitchens with hard water. It is not a single colour, though, and brushed nickel from two manufacturers can differ noticeably in warmth against a main faucet standing next to it. Order the small faucet from the same maker as the main one where possible, or accept that a close match is not an exact one.
Body type comes before finish
Two bodies exist and they are not interchangeable. A standard faucet carries only the treated water line. An air gap faucet carries three connections, routing the reverse osmosis drain up through the body and back down to prevent drain water siphoning back into the system, and some jurisdictions require it. Air gap models also gurgle audibly in normal operation, which surprises owners nobody warned. Establish which your local code requires before choosing anything on looks.
Reach and height, checked physically
The spout must clear the tallest jug or bottle the household actually fills, and must discharge over the bowl rather than towards its edge. It must not clash with the main faucet's handle through its swing. And there must be room underneath for the mounting nut and the tube connections, which is tight where the faucet sits against a sink upstand or a wall. Sit the faucet in position and try it with a real bottle before making the hole.
Making the hole and living with it
Use an existing spare knockout if the sink has one. Otherwise stainless takes a step drill with cutting fluid, granite and quartz need a diamond hole saw with water cooling, and ceramic and enamel crack readily and are best left to a specialist. Afterwards, most drips are the ceramic cartridge inside the faucet rather than the filter system, and it is often replaceable separately. Our faucet filter guide covers the rest of the under sink installation.
Questions people ask about ro faucet brushed nickel
Why is brushed nickel popular for these?
It hides water spots and fingerprints far better than polished chrome, which matters most in hard water areas.
Will it match my main faucet exactly?
Not necessarily. Brushed nickel varies in warmth between manufacturers, so order from the same maker where you can.
Do I need an air gap body?
In some jurisdictions, yes, to prevent drain water siphoning back. Check local code before choosing on appearance.
What should I check before drilling?
That the spout clears your tallest bottle, discharges over the bowl, clears the main faucet handle, and has room underneath.