The Sink and Mirror is a decorative object in prison architect used to satisfy the hygiene needs of a prisoner. Even though it has the ability to do this, it's arguable if you actually want to use this as a primary source of hygiene satiation. The amount of hygiene it satiates in game is incredibly low compared to the shower head for example. Just like the hand dryer it's more useful as a cosmetic/decorative object than a functional one.
The object can only be placed on indoor walls and requires water pipe lines to function.