This Hexagon Wrench structure manhole cover is mainly used in urban main road, freight station, logistics park, gas station and other places. Its bearing capacity can reach the D400 level in the national standard GB/T 23858, and it can pass 80tons. The characteristics are strength toughness, high load capacity, corrosion resistance, high temperature resistant,flame retardant, impact resistant, anti-aging...The material has no recycling value and will not be stolen, which can effectively ensure road safety.