Catalogued as a schematic, this 80.2 KB PDF carries the code 249NQ135, which looks like a power diode or rectifier module part number, so a datasheet is the likely content. The name does not state the manufacturer. Such sheets supply maximum reverse voltage, forward current, thermal resistance and case drawings that matter when replacing a module in a power supply or welder. Read it with any PDF program, and confirm that the full marking on the original part matches before choosing 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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.