The Rex Device is supplied in two ways: as a Rex OEM board to be embedded in a larger system or as a Rex End User Case. See picture below.

The Rex Device uses a 1A fuse on board.
When installing Rex End User Case:
Note on the picture below the back of Rex End User Case in details:

For detailed connector's placement, OEM board dimensions, End User Case dimensions and cabling information see the sections:
After physical installation, power on the device and note if:

If you are experiencing problems to get things working, take a look at Rex2006 Connection Troubleshooter and Rex2006 Firewall Troubleshooter.