Classified as a schematic, this 143 KB PDF is named 444cnq035 and names no brand or device. The code resembles a high-current Schottky rectifier module designation, although that should be confirmed by reading the document. Expect electrical ratings such as reverse voltage, average forward current and forward drop, plus thermal curves and package outline. Such data helps when checking or replacing output rectifiers in larger power supplies; compare the full part marking and mounting style with the sheet before choosing 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.