That is a fine example.
I know for a fact that about 18 months ago a local advance auto magicaly started recieving a purolator filter that was markedly different than the one they had been selling for as long as I've taken notice for the older IDI VW diesel. And you know VW has not changed the filter spec in a lot of years, if ever. I think purolator found a way to cut corners on a low sales volume filter personaly.
It became a hobby of mine, observing filters now and again. Still is to a lesser degree.
One more Radar Lover gone...
1982 VW Caddy diesel 398K 1.9L AAZ
1981 VW Caddy diesel 645K (left back east
1973 w114 280 sedan 133K.. (sold)