The mounting plates are made of solid, galvanized industrial steel. The fastening solution is brilliantly simple: The fastening from the patented Wagner standard system is standardized at its lower end to 8 mm. This allows it to fit into any furniture caster and any furniture glide from Wagner, which also has an 8 mm standard. Here’s how it works: The upper part of the fastening connects to the furniture, while the lower part provides the standardized connection to the caster or glide. Screw it on, plug it in – done! Result: Every fastening fits every furniture caster and every furniture glide!.