I put one on. It was from ABC but they have stopped production. They mention buying
them on ebay now. I don't really like it that much so maybe no big loss if you can't one of theirs. There is a 1/4" bolt in the middle that secures the adapter plate that needs to have the proper torque or it will come loose if you have a tight filter.
The good thing about an adapter is there are a 100 different filters that you can now use. Long, short, drain valves etc. and no mess.