Code 20ETS16S names this 139 KB PDF in the schematic category. No brand, model, board number or revision is stated. The pattern suggests a component variant within a series, with the digits and trailing letter likely marking a rating and package. Open it with any PDF reader to check. Technicians consult such sheets when testing a part in circuit or matching a replacement by voltage, current and footprint. Check the full marking on the original device against the document before ordering a substitute.
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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.