Honda Acura Block Plug Adapter Breather Fitting 10AN Catchcan B Series B16 B18Honda Acura Block Plug Adapter Breather Fitting 10AN Catchcan B Series B18 B16 Honda B Series to 10AN Block Plug Adapter will work for any b series motor which has the black box on the back of the block. It just gives you another port to hook up a catch can. This fitting will come in real handy for those who only want to use one port on the back of the block. You don't have to take off the stock 28mm plug on the back of the block, which can be tough