Headset Battery for CS50, CS55 and CS50-USB - Spare Battery | Poly, formerly Plantronics & Polycom
Replacement Battery for the Plantronics CS50 & CS55
Poly Voyager Focus 2 Uc Usb-c Headset With Stand (plantronics) - Bluetooth Dual-ear (stereo) Headset With Boom Mic - Usb-c Pc / Mac Compatible - Anc : Target
ING Plantronics Spare Battery Extra Battery Life For Headset | eBay