Wireless desk headset system. Connection to the device: EHS adapter, RJ-9. Wearing style: In-ear, Convertible/ear hook/headband, Wearing mode: Mono. Suitable for office use. Microsoft certification: No. Range of up to 100 m. Usable as both an ear hook and headband model. Includes EHS cable APS-11. The cordless headset CS540 from Plantronics' CS family provides greater freedom of movement in the office and allows for effective multitasking, keeping your hands free. Tasks can be completed flexibly and up to 100 m away from the desk. Call control is managed via a multifunction button (answer/end call) and a volume button (with mute function). The included EHS cable APS-11 is used for call control with landline phones. Calls can be made completely without the HL10 handset lifter using this cable.