Not sure if this is the right board, but here goes.
What is the difference between a USB-7856R and a USB-7856R OEM?
John O'C Staff Test Systems Engineer Woodward, Inc. Skokie, Illinois, USA
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming... Wow...What a Ride!"
There are a few differences between the USB-7856R and the USB-7856R OEM. Mainly in the areas of product certifications and available inputs and outputs. I've included a few links below that have some relevant information.