PDF, 250 KB, for the 2SA1255 PNP transistor, with 2SA being the Japanese JIS designation for that class. The index labels it a schematic, but since only the part number is given it is most likely a manufacturer datasheet. Inside you should find pinout, case dimensions, maximum ratings and electrical characteristics. Consult it before replacing a shorted or open device, to confirm orientation and to check that an alternative part provides at least equal breakdown voltage, current capacity and power handling.
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.