This food-grade polypropylene is molded to support filters, false tank bottoms or media. It can be used as benchtops in greenhouses. It is very easy to clean and disinfect. Each plate measures 36" L x 18" W x 1/2" H and is composed of 1" x 1" grid squares. They are durable, lightweight and very resistant to sagging. Interlocking assembly is convenient for connecting grates together. Grates are UV resistant. Each piece weighs 2 lbs. Ships Oversize.