PDF of about 63 KB for part 2SC4618, with a trailing h in the name whose meaning is not stated and may denote a variant or document version. 2SC numbers belong to the Japanese JIS system and identify NPN transistors for high-frequency service. Despite the schematic category this is most likely a datasheet, giving pinout, ratings and package data. Before replacing a component, compare its marking and suffix with the sheet, because variants can differ in gain grouping or package style.
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.