I'm getting ready to purchase this adapter however before doing so I checked Ebay to see if any were available at a lower cost. Since there are I decided I would go that route. Before doing so I wanted to obtain confirmation on the part number. The listing has it as 1067348-00-B with 1067348-00-A being an alternative. I think someone mentioned there were two versions of this adapter with one having a locking ring and the other does not. Is this correct? If so which part number aligns with which version?