Pensla Steels Pvt. Ltd offers Plumb bob round type, which is a weight, accessible with a pointed slant on the bottom. It has been suspended from a string and can be utilized as a plumb-line as well as vertical reference line. This is a precursor to the spirit level, which can establish a vertical as well as horizontal datum. Plumb bob round type are applicable with most of the tall structures so as to provide vertical datum lines for the structure measurements. This weighted object can be connected to a string so as to create a vertical line. This employs the law of gravity so as to make the "plumb".