Component datasheet in PDF, 86.7 KB, for the 2SK546, listed among schematics. Following JIS numbering, 2SK parts are N-channel FETs, so the document covers a single discrete device, likely with ratings, pinout and performance curves. Technicians consult it when a transistor is suspected shorted, to identify gate, drain and source and to compare limits when selecting an equivalent. The name gives no manufacturer, so check the marking on the physical part and its package against the sheet before substituting.
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.