What is the garden manhole cover on the first floor?

Build roads or deep wells at home. Garden manhole covers on the first floor can be divided into metal manhole covers, high-strength fiber cement concrete manhole covers and resin manhole covers according to materials. Usually round. Can be used in green belts, sidewalks, motor vehicles, docks, alleys and so on. Used to cover roads or deep wells at home to prevent people or things from falling.