Diswoe K502QSMA Corded Telephone Headset with NC Mic + All in One Smart Cord for Aastra Nortel Nec Mitel ShoreTel Toshiba Siemens GE InterTel Talkswitch Iwatsu Packet8 ESI Allworx 3Com Office IP Phone 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 Comes with Universal Compatible Smart Cord, Simple 8-position slide adjustment & Standard RJ connector, Connects to 90% desk phones using a standard modular plug. Direct connect headset, no additional amplifier or adapter required. Adjustable fit headband and comfortable ear cushions enhance for wearing comfort, even for long periods. Superior call Center quality headset, excellent sound quality, lightweight, durable and comfortable for all day use Noise canceling microphone to reduce background noise and Acoustic Shock Protection circuit to protect your hearing. 8-position configurations: 1 Standard (most common) M-, R, R, M+ 2 Cisco IP phones 79xx series R, M-, M+, R 3 Ascom offce and Philips phones R, M+, M-, R 4 Japanese phones, NEC, Nitsuko M+, R, R, M- 5 PLT Vista Base R, R, M+, M- 6 Panasonic phones with modular plug M+, R, R, M- 7 Nortel digital phones and Avaya IP phones M-, R, R, M+ 8 Avaya Callmaster V and VI, Cisco R, M-, M+, R