Preface by saying, I don't have a dog in the RP-Amsoil Oil filter comparo hunt. That said, RP's efficiency rating has been discussed often this subforum. With that, RP also claims and has long claimed a rating of "98.7% @ 20 or greater microns". It's on the same RP site shown above and linked below. Scroll to the bottom of link, see bullet point #2. That % is also known as the "absolute rating".
https://filters.royalpurple.com/filters/
Also as can be seen in the linked video, the frequently posted Amsoil graph on the back of the Amsoil OF at ~4:14 in video shows 98.7% @20 um for the Amsoil OF. That would same as the RP rating. Are the filter medias the same? 'Based on the video, Amsoil box info and RP website info,' I couldn't rule it out. Both OFs in the video are made by Champ Labs. The yt is from 2019, relatively recent.
https://filters.royalpurple.com/filters/
Also as can be seen in the linked video, the frequently posted Amsoil graph on the back of the Amsoil OF at ~4:14 in video shows 98.7% @20 um for the Amsoil OF. That would same as the RP rating. Are the filter medias the same? 'Based on the video, Amsoil box info and RP website info,' I couldn't rule it out. Both OFs in the video are made by Champ Labs. The yt is from 2019, relatively recent.
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