It's a USB to NMEA2000 adapter. USB side is an FTDI chip. FTDI talks to an ST STR712FR1, then an isolation barrier, and CAN interface (NCV7351). CAN side of isolation appears to be powered from the CAN bus. There is very little to it, but it is all spread out a lot in an excessively large box.

The NMEA network cable is quite hefty.

Actisense sell an isolated and non-isolated version. The one I looked at says it is the normal USB version but it appears to be isolated inside.

[45957.926270] usb 1-1.2: new full-speed USB device number 11 using ehci-pci
[45958.041185] usb 1-1.2: New USB device found, idVendor=0403, idProduct=d9aa, bcdDevice= 6.00
[45958.041202] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[45958.041207] usb 1-1.2: Product: NGT-1
[45958.041210] usb 1-1.2: Manufacturer: Actisense
[45958.041213] usb 1-1.2: SerialNumber: 37522
[45958.618377] usbcore: registered new interface driver ftdi_sio
[45958.618834] usbserial: USB Serial support registered for FTDI USB Serial Device
[45958.618914] ftdi_sio 1-1.2:1.0: FTDI USB Serial Device converter detected
[45958.618958] usb 1-1.2: Detected FT232R
[45958.620317] usb 1-1.2: FTDI USB Serial Device converter now attached to ttyUSB0