Component sheet, 76.2 KB in PDF, for the 2SC4491 transistor. JIS numbering assigns the 2SC prefix to NPN bipolar devices, and despite the schematic category this is a single-part datasheet. It should give limits, electrical characteristics and the package outline. Repair work uses it for identifying base, collector and emitter, for diode-mode checks and for finding a suitable cross-reference. Match voltage and current ratings at least as high as the original and verify footprint fit.
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.