Material: black anodized aluminium.
Components are attached to the carriers by M6 screws from beneath or from the top through M6 mounting holes.
To release and to move, or to lift the carrier push the lever of the clip. To stop the carrier firmly, use the fixing screw. Rather than grinding against, and damaging the rail with its tip, the screw gently clamps to the rail the wide tenon of the clip.
The clip is preloaded by a spring. Its lever is removable (on a thread). Read the absolute position on the scale engraved on the rail. For quick repeated positioning, you may use a smaller carrier as a reference stop.