The problem of corroding studs and nuts will be common to all machine manufacturer and industrial plants and factoriesValuable timeand money are continually wasted as corroded nuts and studs are attacked with a cutting torch or hacksaw. The parts can be damaged and personnel face a continual risk of injury as they struggle with corroded bolts. These problems are eliminated by the use of nut and thread protectors which fit over the stud and nut and completely seal the assembly from the environment.The RADOLID-System offers essential advantages compared to other cap-systems. With its proved essential advantages compared to other cap-systems. With its principle with locking edge and sealing lip and a circular cross-section the caps do not only guarantee a firm hold on the screw joint but also prevent humidity from soaking into it. Even the use of zinc coated or high-grade steel nuts and bolts do not protect from corrosion but do encourage electrolytic corrosion.