The Person Gesturing OK: Medium Skin Tone emoji is a modifier sequence combining ? Person Gesturing OK and ? Medium Skin Tone. These display as a single emoji on supported platforms.
Person Gesturing OK: Medium Skin Tone was added to Emoji 2.0 in 2015.
U+1F646
U+1F3FD
?? Face with ok gesture
?? Emoji modifier fitzpatrick type-4