Salco Products (TC25N60P1A) 2-1/2-inch Nitronic 60 Plug Assembly with Carbon Steel Chain consists of a plug that has 2-1/2-inch NPT threads and is made out of Nitronic 60 material. The width across the flats of the head is 2-1/2-inches. Length of the thread is 1.06-inches with the overall length of the plug being 2.38-inches. Comes with a carbon steel chain assembly that consists of a 1/4-inch, carbon steel, swivel link that is crimped around the plug, and is connected to a 1/4-inch, carbon steel, chain of 15 links with an approximate length of 19-inches.