I bought JBL headphones and found out they have these holes on both sides. What are they for? They're empty and kinda deep, the headphones aren't wireless so I guess it's not
JBL Tune 510BT | Wireless on-ear headphones
JBL Tune 510BT Headphones - The Only Review You Need to Read - Major HiFi
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JBL TUNE 500BT Wireless On-Ear Bluetooth Headphones- Blue
JBL Tune 510BT Headphones - The Only Review You Need to Read - Major HiFi