?2 YEAR WARRANTY & 2.5MM JACK COMPATIBILITY?: 45 days money back guarantee and 2 years warranty. COMPATIBLE WITH SOME SPECIFIC PHONE MODELS WITH 2.5MM JACK LISTED IN DESCRIPTION (include but not limited). Buy this phone headsets for office phones if you have one of phone models in list. For Other Phones, pls Contact Us for Compatibility Guide or Advice. ?SUPER DURABLE?: Precision design, quality plastics, unibody headband construction, superior quality mic makes this hands-free call center headset sturdier and more durable. Compete with Plantronics or Jabra heavy duty telephone headsets for Call Center Service, Customer Service, Conference Calls, Telemarketing, Telephone Counseling Services, Phone sales, Insurance, Hospitals, Banks, Telecom Operators, Enterprises, Home, Office & Cordless DECT Phones. ?MOST COMFORTABLE HEADSET?: Super lightweight office Phone headset for AT&T Cordless Dect Phones 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. ?HIGH SOUND QUALITY FOR CLEAR COMMUNICATION?: Wideband Sound 2.5mm Landline Phone Headset for Panasonic 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. ?2.5MM TELEPHONE HEADSET?: NOT for Cell phones and Computers ,This Phone Headset with Microphone is ONLY Compatible with AT&T ML17929 Panasonic VTech CM18445 RCA 25424RE1 Uniden Cisco Linksys SPA Grandstream Polycom Clarity XLC3.4 Yealink W52P Zultys Siemens Gigaset Cortelco Home Office Landline Phones and most Cordless Dect Phones with standard 2.5MM HEADSET JACK. SEE MORE COMPATIBLE PHONE LIST IN DESCRIPTION.