Features: 1. Drive-free sound card, upgrade round 2. Two headphones connected at the same time 3. One-click solution at critical moments ORICO SC2 USB multi-function drive-free sound card Model: ORICO SC2 Product Material Engineering Materials Input interface USB2.0 Output interface: Microphone interface, 4PIN headset interface, headphone interface Signal to noise ratio>=80dB Frequency response range 15Hz-25KHz Headphone indicator blue The microphone indicator is red and lights up when muted Other functions mute switch, volume adjustment Support system Windows/Mac OS/Linux Line length 10cmORICO SC2 USB multi-function drive-free sound card Model: ORICO SC2 Product Material Engineering Materials Input interface USB2.0 Output interface: Microphone interface, 4PIN headset interface, headphone interface Signal to noise ratio>=80dB Frequency response range 15Hz-25KHz Headphone indicator blue The microphone indicator is red and lights up when muted Other functions mute switch, volume adjustment Support system Windows/Mac OS/Linux Line length 10cm