Curtis Wagner Plastics MC-800 Plant Mat, Natural Cork, 8-Inch CORK SURFACE - Designed to act as a barrier between planters and flooring or other surfaces. PLASTIC FEET - Plastic bottom and feet (in black). NATURAL CORK - Top made from natural cork, designed for airflow. DURABLE - Designed to stand up to wind and weather and can be used indoors or outdoors. 3/8 thick. MADE IN USA - Product of the United States.