... up to 30, 000 tons, Jiangsu Polycon Co., Ltd has four series of polymer concrete products. They are trench channels, manholes, manhole ... covers and flumes. The products of Jiangsu Polycon Co., Ltd are ... up to 30, 000 tons, Jiangsu Polycon Co., Ltd has four series of polymer concrete products. They are trench channels, manholes, ...