This case is designed to be printed with TPU or some flexible material. The case is meant to be pinched at the sides to open the "mouth" and allow you to grab your earbuds or stow them away. At 100% scale, the case is a good fit for wireless earbuds, and I've found that for standard wired earbuds, scaling the design to 70-75% is best.

I think this is the best style of case for earbuds and wires. No need to wrap the wires up or coil them, just bundle them up and throw them in the case. The case will keep them in place, and untangled.