AUTO EXTRA 618-10255 TORE!

[ZeeOSix]

It also showed that some designs have louvers with top and bottom openings instead of a one way opening.

Most filtets seem to have louvers facing towards the base end and an oppossite set facing towards the dome end. If the the ones facing towards the base don't look good, it gets put back on the shelf. Louvers should be visually inspected before buying if possible, or at least inspected before installation if bought on-line. It's too late after the filter has been used to catch bad louvers.