This product is a USB telephone headset. It is made of solid materials. It is safe and durable. It can serve you for a long time without being easily . It is an excellent USB telephone headset that can bring you more convenience, allowing you to have a more comfortable . Features -Color:Black -Material:PU -Size:15.00X14.00X5.00cm/5.89X5.50X1.97in Interface type: USB 2.0 connector Speaker diameter: 30mm Speaker impedance: 32ohm Speaker frequency response: 20Hz - 20KHz Speaker sensitivity: 115dB Rated output power: 41MW Large output power: 84MW Noise level: <=-78 Dynamic range: >=78 Distortion rate : <=0.1% Stereo crosstalk: <=-52 Microphone sensitivity: -52dB Microphone directivity: omnidirectional Microphone impedance: <=2.2Kohms Microphone frequency response: 50Hz - 15KHz Headphone wire length: 2m - With advanced noise reduction technology, it can provide you with , natural and even in noisy environments. - You can adjust the volume and mute the microphone quickly and easily. - Bendable and adjustable microphones allow you to freely adjust for the best pickup. - Comfortable to wear, ergonomic design, soft ear cups and adjustable headband. - Widely used in call centers, conference calls, dictation, online courses, presentations, etc. Package list: 3 x telephone headset