... environment.3. Light WeightIt weight only 1/3 of cast-iron manhole cover, more expediently transport, install, and rush to repair, ... its under. It gets over the problem of cast-iron and cement manhole cover run, jump, sound. It improves traffic ability ... and gained good reputation.8. Jinmeng burglarproof manhole cover was famous band of manhole cover industry, we will continuously take innovation and ...