This is a Plantronics adapter cable that allows any of the Plantronics CS500 series: Plantronics CS510, Plantronics CS520, Plantronics CS530, Plantronics CS540 and the Plantronics Savi 700 series: Plantronics W740, Plantronics Savi W710, Plantronics Savi W720, Plantronics Savi W730 to be used with a home analog phone line.
Note: Not compatible with older CS50, CS55, CS70n, CS351, CS361, 510S wireless headsets.Not
Note: Not compatible with corded headsets or amplifers like Plantronics M22
Note: wall splitter not included in the TR-11 package. The device is labeled as TR-1.
For more information see Plantronics TR-11 user-guide