A wide and massive ring in the form of a lining for deep tunnels. It consists of many cast iron blocks - tubings. These structures protect the tunnels from rock pressure and groundwater. A real tubing weighs more than a ton, and ours weighs from 10 to 15 grams, depending on the size.
The width of the product is 14 mm, the thickness is 2.1 mm.
The ring is made with a matte finish on the outside and blackening in relief. Inside, it is glossy with a relief of the contour of the segments.