SEE COMPATIBLE PHONE LIST IN DESCRIPTION. 〖Not for Cell phones and Computers〗Direct connect landline telephone headsets with microphone, ONLY WORK for some Specific Phone Models from Avaya Aastra Mitel ShoreTel Plantronics Allworx NEC Aspire Dterm Nortel Packet8 Digium Toshiba, Polycom: SoundPoint 300 301 335 430 450 500 501 550 560 600 601 650 670 CX300 CX500 CX600 CX700 VVX300 VVX310 VVX311 VVX330 VVX400 VVX410 VVX411 VVX500 VVX600 VVX1500. ONLY BUY the item in the list. | SUPERB SOUND QUALITY: Wideband Sound Telephone Headphone for landline phones enables excellent sound quality for natural listening experience, features Noise Canceling Microphone to reduce background noise, Acoustic Shock Protection Circuit to protect your hearing. | MOST COMFORT HEADSET: Ultra lightweight wired hands-free RJ9 office Phone headset with adjustable headband to fit all head sizes, high quality and soft leatherette ear cushion enhance all-day wearing comfort. Professional Mic Mute / Volume Control built in. | ULTRA DURABLE: Precision Design, Quality plastics, unibody headband construction, superior quality microphone makes this call center phone headset with RJ9 jack sturdier and more durable. Compete with Plantronics or Jabra heavy duty Telephone Headset for Call Center, Telemarketing, Office, Business, Phone sales, Insurance, School, Hospitals, Banks, IT Department, Customer Services, Consulting, Conference Calls. | ONLY COMPATIBLE WITH SOME SPECIFIC PHONE MODELS LISTED IN DESCRIPTION (include but not limited). FOR Other Phones, Pls Contact Us for Compatibility Guide or Advice. 45 DAYS MONEY BACK GUARANTEE & 1 YEAR WARRANTY. Any questions, please feel free to contact us.