If the keepers are springs like coat hanger, you probably have Bendix. If they are flat metal in a cross shape, you have ATE. Some have said that this does not always hold true, but over 40 years I have never seen different.1981 300SD Bendix or ATE?

The brand is also cast in the metal.

Later Bendix also has the flat metal style keepers. They're a different size than the ATE.

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Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

There are fat and thinner brake pads. The fat ones will only go on one brand but I do not remember which. The thinner ones work in both.

Interesting info about the later Bendix; did not know that.