Amazon.com: EPOS | Sennheiser Adapt 230 (1000881) Single Sided Headset, Wireless, Dual-Connectivity Bluetooth, USB-A Dongle Included, UC Optimized and Microsoft Teams Certified, Black : Electronics
Sennheiser IE PRO BT Bluetooth Connector IE PRO BT CONNECTOR B&H
Amazon.com: VOXOA BTunes Wireless Bluetooth Adapter for Sennheiser HD518/558/598/569/579/599
Amazon.com: Airfrex Bluetooth Adapter and Wireless Audio Receiver with Microphone and 2.5mm Jack for Sennheiser HD598 / HD598Cs / HD598SE / HD595 / HD599 / HD559 / HD569 / HD579 / HD518 / HD558 Headphones : Electronics
Bluetooth 5.0 Stereo Adapter Wireless Handsfree Receiver For Sennheiser HD 400 Pro 560 S 2.20S 2.30 2.30i 2.30G Headphones - AliExpress
Sennheiser BTD 600 Bluetooth USB Adapter Black – Swiftronics USA
Sennheiser IE Pro BT Adapter – Thomann United States