To provide a hinge having a hinge function of a simplified structure at low cost and easily assembled, which hinge is effective particularly when a pair of plates openable with each other are produced by folding a sheet metal or the plates form a fixed side of the hinge and an openable door.

According to the structure of the hinge, a rod serving as an arbor of the hinge has one or more grooves formed therein, to form two bearings which are circumferentially movable. The concentric bearings having a plurality of splits pinch an internal diameter of a concentric circular shape having splits in the grooves of the mandrel, and a thrusting direction is also positioned.