Powerline Hardware P54-3G (Millennium Part #540309) is an ANSI Class 54-3 guy strain insulator measuring 5-1/2 in x 3-3/8 in with a 5/8 in hole. Installed inline in a guy wire, the porcelain body electrically sections the guy so an energized conductor contacting the guy above the insulator cannot make the lower portion and anchor hazardous to anyone at ground level. Class 54-3 is the standard size for typical distribution and joint-use guy loads. Aerial crews building fiber on shared utility pole lines should install guy insulators per the pole owner's construction standards on every down guy.