Very small 32.3 KB PDF titled 2SK2383, listed in the schematic category but most probably a short datasheet or summary sheet for an N-channel field-effect transistor, as the JIS 2SK prefix implies. No manufacturer, package or ratings appear in the file name. Despite its size it should give the essentials: pin assignment and maximum ratings. Use it to verify a replacement part and to interpret meter readings on a removed transistor, after confirming the component marking matches.
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.