A 98.2 KB PDF named 2SC4634 documents that NPN bipolar transistor and is presumably its datasheet. An LS-variant document sits alongside it in the collection. The name gives no product or board details. JIS numbering places 2SC devices in the high-frequency NPN category. The sheet should cover ratings, hFE ranks, frequency response and outline dimensions. Use it for pin identification, out-of-circuit testing and cross-referencing a substitute before soldering.
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.