I might shed some light here. I have some custom made ear plugs that were made for me at the Dallas Cycle World Show several years ago. Reading about Big Ears, it appears to be the same. They pour a liquid rubber material in you ear, pick your colors (I picked Red for Right and bLack for Left), let it set in your ear to shape, and then pull it and let it dry for a few hours. Then they trim it when you pick it up.
Thank you! Glad to finally join.
I know man. I just loved how they look. They're not practical but they've been okay.