Manhole Covers & Grates suppliered by us are according to standard EN-124 ( A15, b125, C250, D400, E600), GB standard, ASTM standard, DIN standard etc. Material: Cast Iron: GB9439-88, ISO/DP185-88, ASTM A48, DIN1691-85, BS1452-90, etc Ductile Iron: GB1348-88, ISO1083-87, ASTM A536, DIN1693-77, BS2789-85, etc Cast(Welded) Steel: GB700-88, ISO/OP3755-ASTM A27/A487, DIN1681-85, BS1504-84/BS3100-84, etc Size: 1) Square frame with square opening: Overall Size: From 100mm to 1200mm 2) Square frame with round opening : Overall Size: From 200mm to 1200mm