The square VG04004 Hibiscus Matte Stone Vessel Sink has a luxuriously smooth, matte white surface Solid core PMMA construction means you will never see chips or scratches that expose ugly dark sub-layers. Non-porous, stain resistant and fire retardant. Smooth rounded corners for easy cleaning. Sanding Circle (included with all Matte Stone sinks) provides quick and easy removal of stubborn blemishes or marks. Above-counter installation. Standard 1.75-in. drain opening. Sink measurements- Exterior Dimensions: Length: 16-in. Width: 16-in. Height: 4.625-in. Interior Dimensions- Length: 15.375-in. Width: 15.375-in.