Hello, can someone ID these Pagid Pads?

I got them for one of my MBs, but lost the parts box (with the part number) and can't tell where they go. The imprint on the back of each pad reads:

U1904-554/15.0mm

I think I understand the "15.0mm" part ...would like to know the application (or the MB PN, if available).

Many thanks!

__________________
Michael Stoic

1979 450SLC
1989 300SE