Key Features: Includes Smart Cord cable and function, headset cable terminates in RJ09 connector. NO NEED for a separate bottom cable – headset ready to use. Smart Cord includes 7 different settings, some with amplification, to match most desk phones that have a RJ09 headset port, e.g. Yealink, Mitel, Avaya, AudioCodes, Grandstream, Snom, Unify Optimised for VoIP and Unified Communications Big and soft Leatherette ear cushions, foam option in box Excellent Noise Cancelling Microphone Wideband audio ensures a more natural voice Padded T-Bar So light weight, you can wear it all day Technical Specification: Receiving Type: Dynamic moving coil Connection type: RJ09 Microphone Type: ECM Microphone Directivity: Cardioid Wearing Style: Adjustable headband Microphone Boom: 300 degrees adjustable Joint of speaker and headband: 20 degrees rotatable Storage Temperature: -40 Degrees Celsius - 70 Degrees Celsius Frequency: 150-6.8kHz Speaker Impedance (Mono): 150 ohm plus/minus 15% Speaker Sensitivity at 1kHz (Mono): 98 plus/minus 3dB Microphone Sensitivity at 1kHz: -41 plus/minus 3 dB What's in the box Headset, Spare foam ear cushions, User guide, Clothing clip