It is a Quick Disconnect connector. To connect the headset to a USB port, a connection cable (QD to USB) is required, which can be found in the accessories. Please refer to the compatibility list linked on the product.

At the time, I also bought the Poly adapter to connect to my phone. Here is the description of the Poly adapter: The Plantronics adapter cable is suitable for various Plantronics headsets. The cable has a QD plug (Quick Disconnect) and a 2.5 mm plug for connection to DECT telephones, e.g. from Panasonic. Manufacturer Poly Category Headset accessories Manufacturer no. 64279-02 Release date 02/06/2014 Also ordered from digitec. Everything works well, although I had to send the Poly adapter back once because it was defective after a short time. However, I have been using the replacement for some time now and everything works perfectly.

The Poly adapter is for the 2.5mm jack while Apple offers the Iphone adapter for the 3.5mm jack / In this case you would need: Apple Adapter ATS (jack adapter) to connect 2.5mm to 3.5mm and then Apple Adapter Lightning to mini-jack 3.5mm (Lightning, 3.5mm) to connect 3.5mm to the Iphone port.

Unfortunately, I can't answer that. I use the headset with a cable for a wired telephone and not via a LapTop.