Short PDF of about 34 KB tied to the 2SK2128 part number. It is catalogued as a schematic, but with nothing besides the part number in the name it is presumably a datasheet. The 2SK prefix denotes an N-channel field-effect transistor in Japanese JIS numbering, and no brand is named. Technicians check such sheets for maximum drain-source voltage, continuous current, on-resistance and gate threshold, then compare the marking on the failed device before picking an equivalent.
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.