Feature: 1. This 2.5mm office phone headset is 100% compatible with landline phones or cordless Dect phones with a 2.5 mm headset jack. 2. The noise‑cancelling microphone ensures a clear voice, it can filter unnecessary background noise and pick up your voice loudly. 3. You only need to insert the 2.5 mm plug into the headset port of the phone, which is easy to operate. 4. The lightweight, ergonomically designed headset ensures that the phone headset can be worn comfortably throughout the day. 5. This telephone headphone is ideal for business, call center, conference calls, dictation, etc. Specification: Item Type: Headset Model: H600-2.5 Material:ABS Colour: Black Plug Type: 2.5mm Speaker Parameters: Sensitivity: 105±3dB(178mV 1KHz) Voice Coil Impedance: 150±15Ω(1KHZ) Frequency Characteristics: 100Hz-10KHz Distortion: ≤5%(178mV 1KHZ) Microphone Parameters: Directivity: Single Point Sensitivity: –40±2dB(2.0V,2.2KΩ,1KHz) Distortion:≤5%(4.5V 2.2KΩ 1KHZ) Frequency Characteristics:200Hz-6KHz Applicable Device: Landline Phone or Cordless Dect Phone with 2.5mm Headphone Jack. Package List: 1 x Headset1 x Manual