The STANLEY brass plumb bob has solid-brass construction for durability and rust-resistance with a replaceable, long-lasting hardened steel tip. The screw top simplifies attaching string to center of plumb. Features through hole for easy tightening. Polished-lacquer, solid-brass construction is durable and rust-resistant. Replaceable, hardened steel tip is long-lasting. Screw top simplifies attaching string to center of plumb. Through hole for easy tightening.