Composite covers features 1, high strength: Magnesite inspection, has a high compressive strength, flexural, impact resistance, toughness. The product will be crushed and damaged covers the phenomenon of long-term use, can completely eliminate the occurrence of "urban black hole" of the accident. 2, beautiful appearance: Magnesite inspection covers surface pattern design beautiful, bright colors adjustable, beautify the urban environment. 3, easy to use, light weight: only about one-third the weight of cast iron, easy to transport, installation, repair, greatly reducing the labor intensity. 4, security: Magnesite inspection covers no recycling value, natural anti-theft; according to customer needs and has a locking structure, to achieve the well property theft. 5, weather resistance: Magnesite inspection covers by scientific formula, advanced technology, improve technology and equipment so that the product can be used normally at -50 ℃ ~ + 300 ℃ environment. 6, acid, corrosion resistance, abrasion resistance, rolling vehicles, long service life.