KD Tools 2071 KDT-2071 Exhaust and Tailpipe Expander (1-13/16" to 2-1/2")Flare, shape and expand tailpipes to ensure a tight fit and prevent exhaust leaks. Turn handle to adjust the expander to the diameter of the pipe. Place on the end of the pipe and drive with a hammer. Remove tool and readjust, but do not adjust while tool is in pipe. Repeat hammering until desired shape and size are reached.