This set of three exhaust expanders enable the pipe to be extended parallel to allow additional tail-pipes or accessories to be clamped successfully. The three tools cover mild steel exhausts with diameters: 30 - 44mm, 38 - 62mm & 54 - 87mm.The tools will expand the diameter uniformly and also remove any other damage that may have occurred. Can be used on a mild steel maximum thickness of 1.2mm pipe. Hexagon shaft is turned with 16mm spanner.