Welzh Werkzeug 64 Piece Oil Plug Thread Repair Set 3228-WW4 x 

4 x Taps made from HSS (high speed steel) 4341: M13 x 1.5, M15 x 1.5, M17 x 1.5, M20 x 1.5.
20 x Oil drain plugs / sump plugs made from 45CR (4 sizes, 5 pcs for each).
40 x Aluminium washers / sealing rings (4 sizes, 10 pcs for each).