iPhone 7 comes with EarPods that only have a Lightning connector. If you still want to listen through your old headphones?? you can plug them in using a 3.5 mm headphone jack adapter.
NOTE!!! The adapter can only display the iPhone audio.Can't achieve volume control and dial or answer phone call.
Works with all devices that have a Lightning connector and support iOS 8 iOS 9 iOS 10 or later?? including iPod touch??and iPhone.