The “A” ones are made by Mann & Hummel, the previous ones were made by Champion Labs (for quite a while, not sure when they started building M1 filters). IMHO the Champ ones were better, there’s been a couple anecdotal failures of newer ones.Difference between the A and non-A Mobil oil filters ... another rabbit hole branch, lol.
The A suffix filters look to be rated for 20K vs 15K miles for the non-A suffixed filter models.
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Mobil 1™ Extended Performance oil filters, manufactured by Champions Laboratories, Inc., are warranted to be free from defects in material and workmanship.www.mobil.com