Datasheet in PDF form, 315 KB, whose numeric file name gives no hint of the part, manufacturer or device it covers. Open it in any PDF reader to identify the component. A datasheet like this gives pinouts, package drawings, electrical limits and typical application circuits, which help when checking a chip on the board, finding substitutes or confirming expected voltages on its pins. Make sure the part marking on the actual component matches the one documented before relying on it.
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 @ic_mosfet_pdf_datasheets. 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.