Coodio Corded Call Center Telephone Headset [Mute Switch] [Volume Control] RJ9 Monaural Headphone With Mic Microphone [Noise Cancelling] For Desk Phone Office Landline Phones - Silver Hands-free, built-in volume control and mute switch, provides all day comfortable, clarity, durability and convenience for desk telephone office landline phones. Boom-style noise cancelling microphone adjustable for optimum level For very long calls, you can rotate the headset, as the headset is designed for both left-ear and right-ear listening. Excellent for use with Call Center Service, Telephone Counseling Services, Insurance, Hospitals, Banks, Telecom Operators, Enterprises, Office landline phones. Compatible with desk telephone office landline phones with modular RJ9 headset jack.