The nub preventing my ATH-M50 earpiece from rotating too far back broke off and was lost. Saw other methods of fixing this but many required taking the head phones apart or drilling into it. I wanted a quick solution that didn't require much tinkering. Part prints in less than 1 minute and all that needs to be done afterward is super glueing into place. Note - This part does limit the closed folding by about 15 degrees, but it wasn't an issue for me and my headphones still fit in their case.