Zeadio Hands-free Call Center Headset Headphones Ear Phone Desk Telephone with Comfort Fit Headband Noice Cancelling - Silver [1 Year Warranty] 4-pin RJ9(4P4C) plug, NOT RJ11 plug Direct connect over the head headset, no additional amplifiers or adapters required Boom-style microphone adjustable for optimum level Quality sound with the flexible adjustable noise cancellation microphone Includes limited one-year manufacturer Zeadio's warranty