4Call K502J25 2.5 Corded Headset with Noise Canceling Mic for Polycom Cisco Linksys SPA Grandstream Panasonic Gigaset & Zultys Office IP Telephone & Cordless Dect Phones with 2.5mm Headphone Jack WORKS ONLY FOR PHONES LISTED IN DESCRIPTION, BUY ONLY WHEN YOU HAVE ONE OF THE PHONES LISTED. CONTACT US FOR GUIDE IF YOU ARE NOT SURE ABOUT YOUR PHONE COMPATIBILITY BUY ONLY WHEN YOUR PHONE HAS 2.5MM STANDARD HEADSET JACK. CONTACT US FOR GUIDE IF YOU ARE NOT SURE ABOUT YOUR PHONE COMATIBILITY. SEE PART OF COMPATIBLE PHONES IN DESCRIPTION. 2.5mm Direct connect headset, no additional amplifiers or adapters required for office or DECT phones with standard 2.5mm headset jack. Adjustable fit headband and comfortable ear cushions enhance for wearing comfort, even for long periods. With two earpieces and a noise canceling microphone, this headset is ideal for noisy offices. It delivers high quality sound to both ears, enabling you to concentrate fully on the caller with minimal distraction & superior sound pick up. Flexible microphone boom, 270 degree rotatable, which adjusts to suit your preference, you can also choose to wear the microphone on either your right or left side. Long coiled cord stays out of your way by stretching for long reach, and coiling up for regular use, With Mute / Volume Control built in.