SN-120 This new kind of headset has great quality, and it can be greatly used in language lab. It also has great voice quality. Specifications: Loudspeaker diameter: 50Ohm Earphone sensibility: 112 dB ± 3dB Impedance: 32 © ± 10% Frequency range: 20-20KHz Output Power: 20mv Microphone sensibility: 9.7* 6.7mm-56db± 2db Cord Length: 1.8m Insert diameter: Ø 3.5mm