BN-84U GLONASS GPS Receiver Dual GNSS Receiver Module Antenna USB Level Auto-Adapted Baud Rate 5.0V Supply Voltage, 2M Connector for Laptop PC Car Marine Navigation

This one shows up as com-port not as u-blox location proivider. Works as expected.The best: Work an a mac with catalina WITOUT driver !!!Just use cu.usbmodemXXXXX as port and you NMEA software will work.

UBX-M8030-KT inside the unit can receive up to 3 GNSS systems concurrently and which should improve the performance compared to the older chips such as u-blox 7 (VK-162, etc.) which can handle only one GNSS system at a time.One problem with the unit I got is USB A plug is a bit loose and depending on the USB port the device is not recognized. I can workaround it, but it's annoying.

Can’t assess it’s accuracy but it synchronized to GPS as far as I can tell. Used gpsd on Linux to synchronized the system clock.