DIN 5157
DIN 5157 Sets of taps - Sets of 2 taps for pipe threads G 1/16 to G 4 and Rp 1/16 to Rp 4
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/2008
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/2008