| 摘要 |
PURPOSE: A ring earphone is provided to prevent volume change by installing volume control unit in a stopper of the earphone. CONSTITUTION: In a device, a volume control unit is removed from a line of a ring earphone. The volume control unit is built in an earphone stopper. The volume control unit is removed from the line of earphone. Therefore, the earphone wire is not entangled. The volume of the earphone is not arbitrarily changed. |
