It’s a capacitive touch controller that plugs into a USB Type-C port and lets you control the volume on any Windows, Mac, or Linux laptop by sliding your finger across the surface.

Apple removed the volume bar from the iPhone's lock screen a few years ago but you can bring it back now in a few easy steps.

Prior to 2022, the volume slider was a familiar presence on the Lock Screen whenever media was playing. When Apple released iOS 16, however, it removed the control without explaining the reason.