A 3M representative confirmed with me that they no longer offer refills for our reusable 3M Filtrete furnace filter frame that fits inside our American Standard furnace; however, I’m finding third-party replacement options:
Each of these replacement filters has 36-37 pleats (3M Filtrete frame accommodates up to 37) and is 15.55 inches wide (3M Filtrete frame accommodates 15.5 inches and maybe a little more). I will give one a shot and report back later.