The included Cisco Telephone RJ-9/RJ-22 cord plugs into the headset port of the Cisco phone. This cable will ONLY work with the Cisco phones mentioned below.At only 2 ounces the XS 820 phone headset is a premium high-performance headset. With solid construction and a proprietary manufacturing process, this headset will outlast many other headsets. The Ultra Noise Cancelling microphone will cut down on background noises normally heard by customers. If you are looking for a durable pheadset that you can wear all day for help desk applications, call center, office or home office usage this is your headset. Features: High-Quality Modern design 8ft of cord length Lightweight Telephone headset Cisco Compatible Office Phones 7931, 7935, 7940, 7941, 7942, 7945, 7960, 7961, 7962, 7965, 7970, 7971, 7975 6841, 6851, 6921, 6941, 6945, 6961 8811, 8841, 8845, 8851, 8861, 8865 8941, 8945, 89619951, 9971 What's in the box: â XS 820 Phone Headset â Ergonomic Cisco Telephone Interface Phone Cord Cable â Headset travel bag â Spare Foam Cushion â User Manual