The new generation iPhone (iPhone 7 and newer) is no longer equipped with a standard 3.5mm audio input. As a result, you may no longer be able to connect your beloved headphones or mini-jack earbuds to your iPhone. But no worries, this small cable offers the solution. You connect this small Lightning to 3.5mm Jack Adapter to the Lightning connection of your iPhone or iPad and then you connect your old familiar earbuds on the other side of this adapter. You can therefore see this adapter as an intermediate piece between your headphones and iPhone. Even with a new iPhone, you just still use headphones with a mini jack connection.
This is an original Apple accessory.