aa aa These covers are manufacture concrete infill type, bolted, gasket and watertight and tamper proof manhole covers in grey iron and ductile iron. Available in grey and ductile iron Load Rating available: A15, B125, C250, D400, E600 and F900 Our load testing machine can test up to F900 Broad range of patterns available: 300 mm X 300 mm (11.81" X 11.81") clear opening to 1200 mm X 1200 mm (47.2" X 47.2") clear opening Manufactured to EN-124 standards patterns for North and South Europe available New patterns can be developed in six weeks