It is a part that is placed inside the concrete traverse and prevents the direct contact of the binding screw with the concrete traverse and creates electrical insulation between them. Since concrete has weak abrasion and vibration resistance compared to metals. If the binding screw placed in direct contact with concrete causes wear and tear of the concrete walls on the contact surfaces due to the transfer of shocks and vibrations from the rail to the traverse. Therefore, dowels are used as a layer that has good abrasion resistance, vibration and flexibility. Band and concrete travers are used to prevent this from happening.

The nylon dowel is actually a sacrificial layer, while it provides the possibility to open and close the connecting plate in the binding system multiple times. It replaced the healthy nylon dowel. In order to strengthen the concrete wall that is in contact with the nylon dowel, a type of metal spring is used that is connected to the outer wall of the dowel. This spring strengthens the concrete and prevents the concrete wall from falling. The nylon dowel provides the possibility of coming out more easily from the concrete and replacing the healthy dowel. This type is used for subway systems.