Shank button with double tunnels

Most buttons are sewn onto clothing by looping thread through two or more holes. Usually, the holes go all the way through the button, from front to back, meaning the holes and thread are both visible from the front of the garment. A shank button, however, has a protrusion on the back for attaching the button. Shank buttons tend to "stick out" farther from the surface of the garment and appear wobbly because of this protrusion. Tunnel shank buttons, however, have a hole that goes through the body of the button, from side to side, visible only from the back. They have no protrusions, so they can sit flush against the garment, yet from the front they give the uniform, threadless appearance of a shank button.

I designed this tunnel shank button for a Wirt costume (from the cartoon Over the Garden Wall), to look like the buttons on Wirt's cape. I added two tunnels because I wanted the buttons to feel quite steady and not wobble from side to side. I also made the outer ring rather tall so