The USB-RS485 Adapater [datasheet] with booster from Light-O-Rama is designed to allow your PC computer to talk to Light-O-Rama controllers. It connects to your PC via a USB cable. It then has 2 RJ45 output jacks that you then connect to Light-O-Rama controllers, which can be daisy chained together.
Notes:
Board Markings:
USB485D
RTF D-1 94V-0 1237
Light-O-Rama, Inc.
"Alex" --> Who is Alex?
USB485B-V4
Main Components:
USB port (J3)
2 RJ45 ports
Contains USB UART chip marked: ftdi 1147-C gn211291 ft232rl [data sheet]