[waterfilters]

The US-EZ-4 comes with instructions and with the installation parts.

You'll need to drill a hole in your kitchen sink for the drinking water faucet. Many people use the sprayer hole that is already drilled in their kitchen sink since they don't want to drill another hole. We also have dual faucets that are sold separately – they allow regular water and drinking water from the same main kitchen faucet.
Here are the 2 we sell. They are kind of expensive so most people just use the separate faucet for their drinking water.
http://www.waterfilters.net/Dual-Function-HotCold-and-RO-Chrome-Classic-Faucet-FCT-AQUA_p_0-584.html
http://www.waterfilters.net/Dual-Function-HotCold-and-RO-Chrome-Contemporary-Faucet-FCT-MODENA_p_0-857.html