The 3 different fuel filtes for EFI
EFI = Electric Fuel Injection

1. Pre filter
The first filter, the pre filter. Before the fuel enter the pump you can use this both on external and internal fuel pumps. This is sometimes not nesseccary but it's always good to have it there.
2. Main filter
The main fuel filter. Only reffered to as, -fuel filter. This is mounted on the pressure side of the fuel pump. This is the filter people are talkning about when they say fuel filter.
3. Injector filter
Injector filters are the last stage of filtration before the fuel enter the injectors. All this filtering is all about protecting the fuel injectors from dirt. About 8 micron filtration depending on what filter you are using.