Titled 4GBL series, this 104 KB PDF is filed as a schematic but names no device, board or revision. GBL is a package designation used for single-phase bridge rectifiers, with the 4 prefix generally marking the current class, so the sheet likely lists several voltage grades along with dimensions and pin order. Any PDF viewer opens it. Use it when checking a bridge rectifier in a supply for shorts and when choosing a replacement, matching the full code on the part body.
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.