Making a [4-Pole TRRS to 3.5mm Stereo & Mic Adapter (Male to 2x Female)] from an iphone headphone splitter jack?

I want an adapter that merges the microphone and earphone 3.5 mm jacks into a single 3.5 mm jack ( basically I want to build the blue adapter thingy).
The problem is how do I connect the  microphone pins from the 3.5mm jack? That is how do I connect the two leads marked "?" (see the third picture for what I want to achieve.)

PS: I am not sure whether the microphone jack pinout is the same as drawn. Anybody can confirm whether this is right?

Picture of Making a [4-Pole TRRS to 3.5mm Stereo & Mic Adapter (Male to 2x Female)] from an iphone headphone splitter jack?
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https://www.instructables.com/id/Universal-Mini-OM...

I have described in detail about the two pinout standards of the TRRS jack in the above link! What you're trying to do is possible. However, to do that, first you'll have to find out to which TRRS standard your earphone jack belongs to. Then you can simply add separate connections of MIC(MIC and GND) to one female TRRS jack, and the rest connections(GND,LEFT,RIGHT) to another female TRRS jack. There you have it, your own splitter!