HEARING PROTECTION&MULTIPURPOSE: High quality office telephone headset built-in anti acoustic shock circuit to protect your hearing health. This desk phone headset can compete with Jabra or Plantronics or Sennheiser headsets for high frequency use. Best choice for Call Center, Office, Telemarketing, Customer Services, Home, Business, Bank, Insurance, Conference Calls, IT Enterprise and Many More. SUPERB DURABILITY&LIFETIME WARRANTY: Extremely durable Rj9 headset with reliable components structure, professional designed for the toughest call center environment. From raw material to every component we strict control the quality for you from the origin. Lifetime manufacturer warranty and 45 days money back guarantee. Any issue please feel free to contact us, our customer service team will solve for you ASAP. ERGONOMIC DESIGN: Bendable and Rotatable microphone arm allows you adjust the microphone to any talking position, also place the microphone on either side freely. Big and soft ear cushion, no presure no pain to your ear for long time wearing. Click stop adjustable headband perfect fit for all head sizes. EXCELLENT SOUND QUALITY: Call center landline phone headset with outstanding sound quality plus noise-cancelling microphone enables you and called side to hear every word crystal clear. HD Speaker provide you crystal-clear sound quality. Enhanced noise cancelling microphone deliver clear voice transmission even in noisy call center environment. RJ9 TELEPHONE HEADSET COMPATIBLE WITH CISCO IP PHONES: This professional noise cancelling Rj9 telephone headset includes U10 bottom cord adapter compatible with Cisco IP Phones 6821, 6841 6851, 6921, 6941, 6945, 6961, 7821, 7841, 7861, 7931G, 7940, 7940G, 7941, 7941G, 7942, 7942G, 7945, 7945G, 7960, 7960G, 7961, 7961G, 7962, 7962G, 7965, 7965G, 7970 7970G, 7971, 7971G, 7975, 7975G, 7985G, 8811, 8841, 8845, 8851, 8861, 8865, 8900, 8941, 8945, 8961, 9900, 9951, 9971.