DROK 3.5mm Computer Volume Knob Connection: 3 wires with 3 different color jack connector on the item: The wire with green connector -- connect to the computer audio output port; The wire with red connector -- connect to the computer microphone port; The wire with black connector -- connect to the speaker. 2 female jack connectors on the side of the item: The green 1 -- connect to the headphone; The red 1 -- connect to the microphone on the headphone. Audio Switchable: There is a nice switch on the side of the audio volume control knob that toggles between outputting the sound to your headset or the external speaker. You never have to plug or unplug your headset again. Nor will you ever have to mess with your sound settings on the computer again - instead of this awesome, big honking physical knob on your desk. Volume Control: The entire top of the Wire Controller is 1 big, physical volume control knob, you can both control volume of your computer speaker and headset. 1. First end up setting it up so full volume flows out of the computer, 2. then adjust the volume level you actually want using this big knob, which is way easier than hunting for the setting on your computer. No more getting your eardrums blasted out when you accidentally put on headset with the computer volume all the way up. Note: 1. The volume control knob has a very nice smooth feel, please don't force to turn it. 2. Please don't use this item in damp environment, although the product has been packaged with waterproof material, it may also cause damage to the components if used in damp environment for a long time. Package Included: 1x Volume Control Knob