Gold Plated for better sound quality and less loss. Input: 3.5mm 4-position female for headset or earphone. Output 1: 3.5mm 3-positiion male for Headphone Jack on your PC/Laptop.-Output 2: 3.5mm 3-position male for Mic Jack on your PC/Laptop. Oxygen-free copper provide maximum's conductivity and durability. The 3.5mm connector, also known as phone jack, audio jack or jack plug, is a common family of connector typically used for analog signals, primarily audio. Gold-plated connectors ensure optimum sound quality. And bending resistance provides sufficient durability. To ensure proper hardware detection, we recommend that the external headset be plugged into the adapter first, before the adapter is connected to the computer or mobile device.