Interface interface: RS232. Whether the TTL level is converted to RS232 and connected to the computer serial port. RS-232 interface Bluetooth adapter with embedded Bluetooth protocol stack. The main function of the product is to replace the traditional serial cable connection.
eBay
UGREEN USB Bluetooth Adapter Bluetooth Dongle 5.4 Adapter for PC Bluetooth Receiver & Transmitter
Aliexpress UK
Not really sure what this is for. It was purchased from a clearance auction. Appears to be new. Please see photos for details.
eBay
USB Bluetooth 5.1 Adapter Transmitter Receiver Bluetooth Audio Bluetooth Dongle Wireless USB Adapter
Aliexpress UK
Interface: RS232. Support the bluetooth serial port profiles(spp), and with a bluetooth-enabled notebook computer, equipped with a bluetooth adapter, desktop computers. Equipped with a reset button can remove the saved paired device information, and re-paired with the new bluetooth.
eBay
USB Bluetooth 5.3 Adapter Transmitter Receiver Wireless USB Bluetooth Audio Adapter Bluetooth Dongle
Aliexpress UK
Mini hand Corn Peeler Thresher Machine Dry Corn sheller Stripper Tool. Kids Classic Sandal Clogs Lightweight Beach Slip Shoes Slipper Size Xmas Gift UK. This tiny adaptor allows any device with a standard 9-pin serial port to communicate wirelessly.
eBay
AUX Bluetooth Receiver Adapter for Home Stereo System, HiFi 3.5mm RAC Bluetooth Bluetooth Adapter
Aliexpress UK
Interface: RS232. Equipped with a reset button can remove the saved paired device information, and re-paired with the new bluetooth. Adopt bluetooth chip bluetooth 2.1 standard. enhanced ber error rate performance and automatic frequency hopping technology can ensure efficient and secure communication, and has a stronger anti-jamming capability to ensure the stability and reliability of the communication.
eBay
USB Bluetooth Adapter Bluetooth Dongle 5.4 Adapter for PC Bluetooth Receiver & Transmitter for
Aliexpress UK
This tiny adaptor allows any device with a standard 9-pin serial port to communicate wirelessly. • BT578 RS232 Bluetooth adapter x1. • The default Bluetooth role of BT578 adapter is slave, you can change it to master role by sending AT command.
eBay
Bluetooth 5.4 Adapter USB Bluetooth 5.3 Dongle Bluetooth Receiver & Transmitter for Bluetooth
Aliexpress UK
This tiny adaptor allows any device with a standard 9-pin serial port to communicate wirelessly. • The default Bluetooth role of BT578 adapter is slave, you can change it to master role by sending AT command.
eBay
USB Bluetooth 5.4 Adapter Bluetooth 5.3 Dongle Bluetooth Receiver & Transmitter for Bluetooth
Aliexpress UK
RS232 Bluetooth Serial Adapter Communication. Interface: RS232. Bluetooth Protocol: Bluetooth serial port profile (SPP). Master-Slave Module 5V Mini USB. Equipped with a reset button can remove the saved paired device information, and re-paired with the new Bluetooth.
eBay
USB Bluetooth 5.4 Adapter Bluetooth 5.3 Dongle Bluetooth Receiver & Transmitter for Bluetooth
Aliexpress UK