Datasheet for the 1N5391G diode in a 168 KB PDF, filed under schematics. The G suffix marks a vendor variant, frequently a glass-passivated construction, and the larger file size suggests more curves and packaging detail than the plain series sheet. Use it to verify ratings, forward drop and dimensions when replacing a rectifier on a repair job. Suffix meanings vary between manufacturers, so compare the logo and marking on the original part with the document before treating it as an exact match.
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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.