Installed reverse osmosis system under the kitchen sink with basic chrome faucet that includes an air gap. Customer would like a brushed nickel/stainless steel faucet to match that includes an air gap. We would need to return at a later date when we find something that they agree to. This would be something we would have to price out. Let system pressurize for 2-4 hours, check for leaks, then drain all the water out of the storage tank until the faucet is just a trickle. Then let the tank fill again which will take 2-4 hours.