HDSET PHONE S/L The T10 Single-Line Headset Telephone is a stand-alone headset system that includes the Plantronics convertible headset, and standard features such as redial, flash and mute. The T10 Headset Telephone features a headset rather than a traditional telephone handset, making it ideal for telephone-intensive SOHO applications. The T10 Headset Telephone connects to a standard telephone jack.