OK here's the answer. It's a stock fuel filter bowl delete item. You remove the stock fuel filter and replace it with the aluminum block then tighten the black lid. The center bore fits on the standpipe and the side bore allows fuel to flow toward the engine. It's purpose is to allow me to have separate filters for each fuel that I run. All the sensors on the FPR still work! I'll be installing a Racor water separator filter for my rear tank and have a separate filter for my veggie oil. The problem is that in my current configuration the veggie oil flows through the veggie filter then through the engine filter. When I switch to rear fuel, the engine filter has a coating of veggie oil and causes an unnecessary restriction. This is why I had all my engine filters for sale. Thank goodness I sold out of them. But the biggest benefit of the aluminum block is that it displaces 95% of the volume of the fuel bowl so when I flip tanks to purge the fuel, my purge time has been cut dramatically...from 10 miles to 1 mile.