A 72.5 KB PDF for the 6F(R) series, a rectifier diode family where the R variant conventionally indicates reverse polarity, with the stud or case as anode instead of cathode. No device or board is named, so treat it as a component datasheet. Expect voltage grade tables, forward characteristics and mechanical drawings. Polarity matters here: fitting the wrong variant into a stud-mounted rectifier assembly will reverse the circuit. Check the exact marking on the original part before ordering a replacement.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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