USB Bluetooth-Compatible Adapter V4.0 Dual Mode Wireless Dongle CSR 4.0 USB 2.0 Transmitter Audio Receiver For Windows 10 8 7 - AliExpress
USB Bluetooth 4.0 Low Energy Micro Adapter with CSR8510 Controller and CSR Harmony for Windows XP Vista 2003 2008 Win 7, DS-2 - AliExpress
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How to install the CSR 4.0 Bluetooth adapter driver? – zexmte
New Mini Usb Bluetooth 4.0 Adapter With High Speed Up To 3mbps Csr4.0+edr Csr Dual Mode Receiver For Windows 10/8/7/xp V4.0 - Wireless Adapter - AliExpress
Amazon.com: Bluetooth CSR 4.0 USB Dongle Adapter, EKSEN Bluetooth Transmitter of Electronic Signals for Windows 10/8/7/Vista - Plug and Play on Win 8 and Above - White : Electronics