square manhole cover with double seal type factory
1. material: ductile iron 500-7
2. class:D400 to EN124
3.frame weight: 50kg
4.cover weight:70kg
5.over all dimensions:800*800*100MM
6. clear opening:550*550MM
7. lifting holes: through(plugged with removable rubber stoppers)
8. frame and cover coating : black bituminous.
thickness: 350μm
9.COVER AND FRAME: DOUBLE SEAL TYPE