This round kitchen copper sink has a standard 3.75" diameter hole at the bottom center, it fits the 3.5" diameter drainage size. The rim around it is about 1.5", so the internal dimension is 15" diameter x  8" depth. The bottom diameter is about 10.5". The copper sheet is 18 gauge (0.04" thickness). The finish is in weathered copper, which is antique-looking. MPORTANT NOTE: The patina can be damaged faster if abrasive substances are used to clean it, because of this, we recommend rinse it with water and soap only!