The tubular connectors RV is made up of chill casting of high-grade aluminum alloy. It's in accordance with DIN 1725. Its surface treatment is composed of rough state, drum polished, high-gloss polished, vibratory ground, dull finished and technically anodized. It has power-coatings and its tubular connectors are supplied with sockets nuts and bolts made of stainless steel (material no. 1.4301).