I bought a lens board on ebay only to find out it's much to big for my Calumet 4x5. The seller specified that the board is made for a Calumet 4x5, it says "Calumet" across the top, but the lens board covers the entire front of the camera, much more than the lens board opening.

What specifications do I need to look for in buying the correct lens board? What are the measurements? Did I buy a lens board for an 8x10?