The 12CWQ06FN part number is the only detail this 130 KB PDF name carries, so it is best treated as a component datasheet rather than a circuit drawing. Its format matches the International Rectifier style of rectifier part naming, and sibling files for other voltage grades share the same size. A technician checks it for reverse voltage, average current and pin layout when replacing a failed diode in a power supply section, and should match the full marking on the part before trusting 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.