【NOT for Cell Phones and Computers】: ONLY COMPATIBLE with Plantronics M10, M12, M22 & MX10 Amplifiers or Some Specific CISCO IP phone models: 6821, 6841, 6851, 6921, 6941, 6945, 6961, 7811, 7821, 7841, 7861, 7912, 7920, 7931G, 7940, 7940G, 7941, 7941G, 7942, 7942G, 7945, 7945G, 7960, 7960G, 7961, 7961G, 7962, 7962G, 7965, 7965G, 7970, 7970G, 7971, 7971G, 7975, 7975G, 8811, 8841, 8845, 8851, 8861, 8941, 8945, 8961, 8865, 8941, 8945, 8961, 9951, 9971. | 1-YEAR WARRANTY & COMPATIBILITY NOTES: 45 DAYS MONEY BACK GUARANTEE & 1 YEAR WARRANTY. ONLY COMPATIBLE WITH SOME SPECIFIC PHONE MODELS LISTED IN DESCRIPTION (include but not limited). NOT compatible with Cisco SPA phone series. For Other Phones, Pls contact us for Compatibility Guide or Advice. | CRYSTAL CLEAR CHAT: Wideband Sound RJ9 Call Center Phone Headset with microphone Compatible with Cisco 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: Super lightweight wired Hands-free RJ9 Telephone Headset Compatible with Cisco Desk 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. | ULTRA DURABLE: Precision design, quality plastics, unibody headband construction, superior quality microphone makes this office phone headset with RJ9 jack sturdier and more durable. Compete with Jabra heavy duty Telephone Headphones for Call Center, Office, Home, Telemarketing, Business, Phone sales, Insurance, School, Hospitals, Banks, IT Department, Customer Services, Consulting, Conference Calls.