Johnson 8 oz. Brass Plumb Bob with Replaceable Tip & Removable Cap is used by excavation contractors, foundation contractors, and surveyors for lining up and transferring points. It features a lacquered finish and is made in China. The plumb bob is used for finding a plumb (vertical) line over a long distance. It is made of high-quality plated brass, lacquered with replaceable hardened tips. The removable cap allows for quick, easy, and accurate centered string installation.