Constructions was establised in 2007 in Xiamen City Fujian Province. CM is a worldwide patented system. CM is the first company to produce manhole covers in composite material with high loading capacities to D400. Cover is manufactured from polyurethane reinforced with fiber glass, frame consists of polypropylene reinforced with glass fibers,and sheet mould compound,bulk moulding compound,CM has a range of covers with loading class A15, B125 C250 and D400 but also special products.You will find more details in this website.