Extended Traffic Light Timing mod set longer timing signal to the traffic lights. The traffic light timing modifications are consist of:

24 seconds green light signal interval. (26 seconds in certain countries)
4 seconds yellow signal interval after the green light, before turned red.
2 seconds yellow signal after the red light, before turned green. (only at certain countries. also see "Light Sequences" section)
2 seconds interval between traffic light pattern switching.
Note: The red signal interval may vary depend on the traffic light pattern complexity.
Additional modifications are:

Dimmer traffic light's bulb lamp while light is OFF.
Longer refuel time at gas station for AI vehicles (cars and trucks).
Longer border document check time (applies differently for cars and trucks).
Faster opening barrier by using additional mod (toll booth & border check).

Credits
madman271