No Tarnishing. No Discoloration. No Worries!Brilliance finishes, designed to not corrode, tarnish or discolor for a “like-new" look for life, are developed by embedding molecules deep into the faucet’s surface, creating a bond that is virtually indestructible. This process is known as Physical Vapor Deposition (PVD). Delta was the first manufacturer to offer this patented process that creates a bond that's virtually indestructible with an incredibly reflective shine. Brilliance resists abrasions and discoloration better than traditional special finishes and, in many cases, better than chrome.In independent tests using the harshest drain cleaners, the Delta Brilliance drain retained its appearance, while its competitors did not come close. Tested with over 100 household cleaners, the abrasion resistance of the Brilliance finish can even withstand repeated scouring with steel wool. A Brilliance finish is guaranteed not to corrode, tarnish or discolor for as long as you own your home. It can even withstand prolonged exposure to harsh coastal environments.