6 Plumb Bob's by Starrett. 1 or 2 are the 177D, 1 is the 177B and the rest are the 177C. Exact numbers may be off. These go for $101 to $119 apiece new. I will do $60 a piece or $250 for all. The Starrett steel plumb bob is used to achieve precise accuracy in all layout work, construction and surveying. Solid steel construction provides a low center of gravity and great weight in proportion to their short length and small diameter. Hexagonal shaped head prevents rolling. Hardened and ground removable point for greater accuracy, longer life. Sure grip knurling on polished steel body for easy handling. Easily replaced if worn or broken