... appearance, modern-styled.2.Optimal drainage: Leaking area can reach 83.3%, which is as twice as ... specifications can meet all demands of shapes, sizes, spans, load capability in different conditions.1. Drainage cover with ... type: steel grating hinged pit covertheftproof design: the cover and the frame are connected with hinges, so ... 5. Installation type: galvanized U type steel I bar grid ditch cover