Corner With Trough Tube 90°. Often used on intermediate rail corners to match Type 18 as the tube passes through the clamp.
Another big plus of the black coating is, that the color gets into the material really deeply, which prevents the connectors from corroding. The paintwork is not resistant to UV radiation and is therefore not suitable for outdoor use. The tube fittings are equipped with black-colored stainless steel adjusting screws with cutting edge.