Plantronics 86009-01 Telephone Savi Series Interface CablePlantronics Phone Interface Cable for Savi Series Product # 86009 01 The Plantronics 86009 01 is a telephone Interface cable for Savi Office and CS500 Series Wireless Headsets Systems. It's 4 pin modular end plugs into handset port or headset port of desk phone while RJ45 end plugs into back of wireless charging base. The telephone handset plugs into middle of the cord. 86009 01 Features: Telephone Interface Cable For Savi Office & CS500 Series