When replacing the fuel filter on certain VAG diesel models it is important upon reassembly that the filter lid is presented squarely to the filter body as it is pressed down to seal the integral O-ring.
If the lid is not pressed squarely there is a good chance the O-ring can roll out of its retaining channel and lead to both fuel leaks and under certain circumstances, air ingress at the joint.
The tool features the third generation adaptor which fits more filter housing variants and also offers hands-free use when compressed. This last point is important as VAG guidelines specifically advise against using the type of compressor tool that levers against the fragile inner wing panel work.
The hands-free feature lets you fit the retaining screws while the lid stays compressed to the filter housing — particularly useful if it is the spring-loaded version.
See the diesel fuel filter compressor tool in action on the Tool Connection YouTube channel.