polymer concrete drainage sink gutter grate The products are of high cost performance and have acquired CE ... 000 tons, Jiangsu Polycon Co., Ltd has four series of polymer concrete products. They are trench channels, manholes, manhole covers and flumes. The ... 000 tons, Jiangsu Polycon Co., Ltd has four series of polymer concrete products. They are trench channels, manholes, manhole covers and flumes ...