This is the big central button on an Alpine IDA-x001. This was a car audio head unit from the early 2000s that connected to an ipod. I lost my center button and I made this one to replace it. There are some tight tolerances on the original design and I loosened them up to make it 3D printable. The tightness and smoothness of the fit added to the tactile feeling of the button which is kind of lost on my replacement. But it is better than nothing.