Siemens Simatic Net IE FC M12 Plug PRO 4x2 CAT 6A Compact Operating Instructions page 24

13. Pay attention to the coding.
14. Make sure that the wire pairs are perpendicular to the wire manager as shown
in the following figure. Unfold the wings and pull them out for more leverage.
Press the wings in the direction of the arrow.
IE FC M12 Plug PRO 4x2 CAT 6
A
24 A5E48000311-AA, 08/2019