Locally AZ stores have in the vast majority of STP spin on OFs, moved back to Champ Labs US made filters. I have noticed a few applications that still have whatever/whoever manufacturer with China coo. As mentioned by bbhero the XL was very similar to a Premium Guard filter. Before the move to off shore, Champ Labs was the STP manufacturer, blue can value tier same as old Champ Labs made Super Tech line. Many ecores.
Hadn't seen/noticed the "Tennessee" deal, but as AZ headquartered in Nashville iirc, likely where derived. They used to have another AZ name on box too, Best Brands?, something like that.