PDF file of 177 KB dedicated to the 2SA1426, a part whose 2SA prefix denotes a PNP transistor under the Japanese JIS system. The name states only the part number. Although listed as a schematic, the content is likely a manufacturer data sheet with ratings, characteristics and a mechanical drawing. A technician uses it to identify leads, check whether measured junction behaviour is normal and choose a replacement. The package marking on the original component should match before relying on the pinout shown.
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.