This is a conversion adapter cable that allows you to connect a 4-pole plug microphone-equipped earphone for smartphones and tablets to a PC with two 3.5mm stereo mini jacks (microphone input and headphone output). Since this is an unused item, please understand that we cannot guarantee its operation or provide any warranty. Compatible Devices: [Terminal Devices] PCs with two 3.5mm stereo mini jacks (microphone input and headphone output). *Not compatible with Apple computers. [Microphone-equipped Earphones] Models with a 3.5mm 4-pole mini plug that conforms to the CTIA standard. *The control functions of the microphone-equipped earphones, such as the mute button and call button, are not supported. *We do not guarantee the operation of all devices with 3.5mm 4-pole mini specifications. It may not function properly depending on the device or environment. *To prevent recognition errors or malfunctions, please insert the microphone-equipped earphones into this product first, and then connect it to the terminal device. The shipping method may be changed to Yu-Yu Mercari delivery. Thank you for viewing.