Features: UNCTION - Restore threads to original condition, eliminating the need for thread cutting equipment. EASY TO USE - Tighten the tool slightly on the good threads then back off over the damaged thread area to restore the threads. INCLUDE THREE DIES - 1 mm- 1.25 mm-1.5 mm-1.75 mm; 2 mm-2.5 mm-3.0 mm-3.5 mm; 4 mm pitch dies.( Outer Diameter). MATERIAL - Made of heavy duty steel, resisting deformation, high temperature and corrosion. .