Basically the same thing. The missing three pins on the bottom row in this picture are in parallel with the volume control, with the Lionel model it was designed to be connected to an external pot. You can actually buy the 10K pot and drop it into the holes and use this like the ERR board. The documentation for the old RS Commander is useful if you're using this board. Also, note that the back of the board has a lot of legends for the pins.
If you buy these from Lionel, test them right away, a couple of us got bad ones from Lionel parts and didn't know for months. 
Note that these are NOT compatible with the RailSounds 6 modular sound boards, but they work fine with RS4, 5, and 5.5 boards.
