DOWNLOADS
You can view then download the latest User Guides for the Wireless Headset Interface, Graphic Equaliser Kit and for compatible Plantronics Wireless Telephony Headsets here.
WIRELESS HEADSET INTERFACE User Guide:

WIRELESS HEADSET INTERFACE USER GUIDE V4.2 - 2020 models onwards |

WIRELESS HEADSET INTERFACE USER GUIDE V3.3 - 2011 to 2019 models |
GRAPHIC EQUALISER ADD-ON KIT USER GUIDE:

GRAPHIC EQUALISER ADD-ON KIT USER GUIDE V2.0 |
Plantronics Wireless Headset systems Product Datasheets:

POLY SAVI 8400 SERIES PRODUCT DATASHEET |

PLANTRONICS SAVI 8200 SERIES PRODUCT DATASHEET |

PLANTRONICS SAVI 700 SERIES PRODUCT DATASHEET |

PLANTRONICS CS500 SERIES PRODUCT DATASHEET |
Plantronics Wireless Headset systems User Guides:

POLY SAVI 8410 / 8420 OFFICE USER GUIDE |

PLANTRONICS SAVI 8210-8220 OFFICE USER GUIDE |

PLANTRONICS SAVI W710A/W720A USER GUIDE |

PLANTRONICS SAVI W300 SERIES USER GUIDE |

PLANTRONICS CS510/CS520 USER GUIDE |

PLANTRONICS SUPRAPLUS CS361N USER GUIDE |