Just to clarify the photo above, the rubber for the PF58 is not a valve, just a spacer. It a hard rubber.
The other 2 filters, 59 and the Fram, the rubber is a valve, teh 59 is very soft and the Fram is much harder. It blocks the holes in the filter base preventing flow when engine is not running on the 59 and Fram.
The other 2 filters, 59 and the Fram, the rubber is a valve, teh 59 is very soft and the Fram is much harder. It blocks the holes in the filter base preventing flow when engine is not running on the 59 and Fram.