FreeTalk Talk-5204 Mono Headset with USB and Microphone - Black Mechanics: 40mm speaker driver; Ear pad material: foam Connectivity Technology: USB interface; USB 2.0 Audio compatible; Cable length: 180cm Earpiece: Diaphragm: PET mylar; Frequency response: 20 Hz ~ 20K Hz; Signal-to-noise ratio: 80 dBA; Max Sound pressure level: 95 dBSPL; Total Harmonic Distortion: &lt;5% Microphone: Omnidirectional; Mic position: Boom close to mouth, hanging in wire, built in earpiece; Microphone Impedance: 2K Ohms Frequency response: 100 Hz ~ 8K Hz;Signal-to-noise ratio (SNR): 65 dBA; Maximum SPL: 90 dBSPL; Sensitivity: -32 dBV/Pa;