With the exception of a BNC connector and the distinct lack of a mounting bracket, that EBAY auction is showing the same MacCon card my SE/30 has long used. Works great. I wouldn't pay the $55 BIN though. Not worth that. You'll find these cards on EBAY about once a week, so even if you fail to win this auction, it's not like you'll never seem them again or for a long time. They appear all the time. They are certainly NOT "rare." But then again, I find that very few things are "rare" on EBAY, despite what the sellers may claim.