OVHS072-SYN the OvisLink Single Ear Call Center Headset model for AT&T Syn248 Business phone models SB35024 and SB35031. It is designed to be directly connected to Syn248 Business phone Xblue IP7g, X3030, X4040 phone sets' headset jack. No amplifier is needed. Headset volume can be controlled by the volume buttons on the phone's keypad. To activate or deactivate the headset connected with the phone, simply press the headset button on the telephone keypad. This OvisLink Call Center headset is a corded call center headset with Over-the-Head design. With its flexible and rotatable microphone boom, user may place the speaker on the left or right ear any time. The headset also comes with Acoustic Shock Protection (when the electric overcharge signal of 6v or above comes to the receiver, it will be cut off automatically), Noise Cancellation, lightweight, leatherette ear cushion, rotatable microphone boom, manageable microphone stem, adjustable headband and Tangle-Free coiled Quick Disconnect cord. OvisLink Call Center Headsets are designed for users who work in call centers, service centers or sales departments and talk long hours on the phone. OvisLink Call Center Headsets service users with solid, superior clear sound quality and all-days comfort. (* AT&T has many different telephone models. This headset is only compatible with Syn248 Business phones model SB35025 and SB35031. If you have AT&T SynJ phones, order OvisLink headset model OVHS072-ATT ASIN # B01LORJD8W instead.)