JJP headphone jack & volume control assembly.
 
Usually JJP will make these to order, we need to know what game you are putting it on, they will decal it to match the game. 

This also enables a pair of headphones to be linked via Bluetooth.
 
Machine Compatibility List:
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Elton John
Godfather
Gun N' Roses
Harry Potter
Toy Story
Jersey Jack Pinball #51-100113-00.